The Collaborative International Dictionary of English v.0.48:

Descent \De*scent"\, n. [F. descente, fr. descendre; like vente,
   from vendre. See Descend.]
   1. The act of descending, or passing downward; change of
      place from higher to lower.
      [1913 Webster]

   2. Incursion; sudden attack; especially, hostile invasion
      from sea; -- often followed by upon or on; as, to make a
      descent upon the enemy.
      [1913 Webster]

            The United Provinces . . . ordered public prayer to
            God, when they feared that the French and English
            fleets would make a descent upon their coasts.
                                                  --Jortin.
      [1913 Webster]

   3. Progress downward, as in station, virtue, as in station,
      virtue, and the like, from a higher to a lower state, from
      a higher to a lower state, from the more to the less
      important, from the better to the worse, etc.
      [1913 Webster]

   2. Derivation, as from an ancestor; procedure by generation;
      lineage; birth; extraction. --Dryden.
      [1913 Webster]

   5. (Law) Transmission of an estate by inheritance, usually,
      but not necessarily, in the descending line; title to
      inherit an estate by reason of consanguinity. --Abbott.
      [1913 Webster]

   6. Inclination downward; a descending way; inclined or
      sloping surface; declivity; slope; as, a steep descent.
      [1913 Webster]

   7. That which is descended; descendants; issue.
      [1913 Webster]

            If care of our descent perplex us most,
            Which must be born to certain woe.    --Milton.
      [1913 Webster]

   8. A step or remove downward in any scale of gradation; a
      degree in the scale of genealogy; a generation.
      [1913 Webster]

            No man living is a thousand descents removed from
            Adam himself.                         --Hooker.
      [1913 Webster]

   9. Lowest place; extreme downward place. [R.]
      [1913 Webster]

            And from the extremest upward of thy head,
            To the descent and dust below thy foot. --Shak.

   10. (Mus.) A passing from a higher to a lower tone.

   Syn: Declivity; slope; degradation; extraction; lineage;
        assault; invasion; attack.
        [1913 Webster]

WordNet (r) 3.0 (2006):

descent
    n 1: a movement downward
    2: properties attributable to your ancestry; "he comes from good
       origins" [syn: origin, descent, extraction]
    3: the act of changing your location in a downward direction
    4: the kinship relation between an individual and the
       individual's progenitors [syn: descent, line of descent,
       lineage, filiation]
    5: a downward slope or bend [syn: descent, declivity,
       fall, decline, declination, declension, downslope]
       [ant: acclivity, ascent, climb, raise, rise,
       upgrade]
    6: the descendants of one individual; "his entire lineage has
       been warriors" [syn: lineage, line, line of descent,
       descent, bloodline, blood line, blood, pedigree,
       ancestry, origin, parentage, stemma, stock]

Moby Thesaurus II by Grady Ward, 1.0:

309 Moby Thesaurus words for "descent":
   Brownian movement, Indian file, abasement, advance, affiliation,
   altitude peak, angular motion, apparentation, array, articulation,
   ascending, ascent, automatic control, axial motion, backflowing,
   backing, backset, backward motion, bank, birth, blast-off, blood,
   bloodline, branch, breed, brood, burn, burnout, buzz, career,
   catena, catenation, ceiling, chain, chain reaction, chaining,
   characterize, check, children, climbing, comedown, coming after,
   common ancestry, communicate, concatenation, concavity, connection,
   consanguinity, consecution, consecutiveness, construe,
   continuation, continuity, continuum, course, current, cycle,
   de-escalation, debasement, decadence, decadency, declension,
   declination, decline, declivity, deflation, deformation,
   degeneracy, degenerateness, degeneration, degradation, delineate,
   demotion, depict, depravation, depravedness, depreciation,
   depression, derivation, derogation, descendants, descending,
   describe, deterioration, detrusion, devolution, diminution, dip,
   direct line, discomfiture, disgrace, distaff side, distinguish,
   down, downgate, downgrade, downhill, downtrend, downturn,
   downward mobility, downward motion, downward trend, drift,
   driftage, drone, drop, ducking, dump, dying, ebb, ebbing,
   effeteness, elucidate, embarrassment, end of burning, endless belt,
   endless round, exemplify, explain, explicate, expound, extension,
   extraction, fading, failing, failure, failure of nerve, fall,
   falling-off, family, female line, file, filiation, flight, flow,
   flux, following, forward motion, fruit, gamut, gradation, grade,
   gradient, grandchildren, great-grandchildren, hang, hangdog look,
   hanging, hauling down, heirs, hollowness, hostages to fortune,
   house, hum, humbled pride, humiliation, ignition, illustrate,
   image, impact, impart, incline, inheritors, interpret, involution,
   issue, kids, lapse, launch, letdown, lift-off, limn, line,
   line of descent, lineage, little ones, logical sequence,
   loss of tone, lowering, male line, monotone, mortification,
   mounting, narrate, new generation, nexus, oblique motion,
   offspring, ongoing, onrush, order, order of succession, origin,
   passage, pedigree, pendulum, periodicity, phylum, picture, plenum,
   plummeting, plunging, portray, posteriority, posterity,
   postposition, powder train, procession, progeny, progress,
   progression, prolongation, put-down, queue, race, radial motion,
   random motion, range, rank, recite, recount, recurrence, reduction,
   reflowing, refluence, reflux, regression, rehearse, render, report,
   reticulation, retrocession, retrogradation, retrogression,
   reversal, reverse, reverse of fortune, rise, rising,
   rising generation, rocket launching, rotation, round, routine, row,
   run, rush, scale, seed, self-abasement, self-abnegation,
   self-diminishment, sept, sequence, series, set, setback, setdown,
   severe check, shame, shamefacedness, shamefastness, shoot, shot,
   side, sideward motion, single file, sinking, slippage, slope,
   slump, soaring, sons, spear side, spectrum, spindle side, state,
   stem, sternway, stirps, stock, strain, stream, string, subjunction,
   submergence, subsiding, succession, successiveness, suffixation,
   swath, sword side, thread, throwback, thrusting under, tier, train,
   traject, trajectory, trajet, transmit, treasures, trend,
   upward motion, velocity peak, wane, windrow, younglings,
   youngsters



Bouvier's Law Dictionary, Revised 6th Ed (1856):

DESCENT. Hereditary succession. Descent is the title, whereby a person, upon
the death of his ancestor, acquires the estate of the latter, as his heir at
law: This manner of acquiring title is directly opposed to that of purchase.
(q.v.) 2 Bouv. Inst. n. 1952, et seq.
     2. It will be proper to consider, 1. What kind of property descends;
and, 2. The general rules of descent.
     3.-1. All real estate, and all freehold of inheritance in land,
descend to the heir. And, as being accessory to the land and making a part
of the inheritance, fixtures, and emblements, and all things annexed to, or
connected with the land, descend with it to the heir. Terms for years, and
other estates less than freehold, pass to the executor, and are not subjects
of descent. It is a rule at common law that no one can inherit read estate
unless he was heir to the person last seised. This does not apply as a
general rule in the United States. Vide article Possessio fratris.
     4.-2. The general rules of the law of descent. 1. It is a general
rule in the law of inheritance, that if a person owning real estate, dies
seised, or as owner, without devising the same, the estate shall descend to
his descendants in the direct line of lineal descent, and if there be but
one person, then to him or her alone; and if more than one person, and all
of equal degree of consanguinity to the ancestor, then the inheritance shall
descend to the several persons as tenants in common in equal parts, however
remote from the intestate the common degree of consanguinity may be. This
rule is in favor of the equal claims of descending line, in the same degree,
without distinction of sex, and to the exclusion of all other claimants. The
following example will, illustrate it; it consists of three distinct cases:
1. Suppose Paul shall die seised of real estate, leaving two sons and a
daughter, in this case the estate would descend to them in equal parts; but
suppose, 2. That instead of children, he should leave several grandchildren,
two of them the children of his son Peter, and one the son of his son John,
these will inherit the estate in equal proportions; or, 3. Instead of
children and grandchildren, suppose Paul left ten great grandchildren, one
the lineal descendant of his son John, and nine the descendants of his son
Peter; these, like the others, would partake equally of the inheritance as
tenants in common. According to 'Chancellor Kent, this rule prevails in all
the United States, with this variation, that in Vermont the male descendants
take double the share of females; and in South Carolina, the widow takes
one-third of the estate in fee; and in Georgia, she tales a child's share in
fee, if there be any children, and, if none, she then takes in each of those
states, a moiety of the estate. In North and South Carolina, the claimant
takes in all cases, per stirpes, though standing in the same degree. 4 Kent,
Com. 371; Reeves' Law of Desc. passim; Griff. Law Reg., answers to the 6th
interr. under the head of each state. In Louisiana the rule is, that in all
cases in which representation is admitted, the partition is made by roots;
if one root has produced several branches, the subdivision is also made by
root in each branch, and the members of the branch take between them by
heads. Civil Code, art. 895.
     5.-2. It is also a rule, that if a person dying seised, or as owner
of the land, leaves lawful issue of different degrees of consanguinity, the
inheritance shall descend to the children and grandchildren of the ancestor,
if any be living, and to the issue of such children and grandchildren as
shall be dead, and so on to the remotest degree, as tenants in common; but
such grandchildren and their descendants, shall inherit only such share as
their parents respectively would have inherited if living. This rule may be
illustrated by the following example: 1. Suppose Peter, the ancestor, had
two children; John, dead, (represented in the following diagram by figure
1,) and Maria, living (fig. 2); John had two children, Joseph, living, (fig.
3,) and Charles, dead (fig. 4); Charles had two children, Robert, living,
(fig. 5,) and James, dead (fig. 6.); James had two children, both living,
Ann, (fig. 7,) and William, (fig. 8.)

                     Peter (0) the ancestor.
                         ³
          ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
          ³                                       ³
       (1) John                                (2) Maria
          ³
   ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
   ³                         ³
(3) Joseph                (4) Charles
                             ³
               ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
               ³                     ³
            (5) Robert            (6) James
                                     ³
                     ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿
                     ³                     ³
                  (7) Ann               (8) William

     In this case Maria would inherit one-half; Joseph, the son of John,
one-half of the half, or quarter of the whole; Robert, one-eighth of the
whole; and Ann and William, each one-sixteenth of the whole, which they
would hold as tenants in common in these proportions. This is called
inheritance per stirpes, by roots, because the heirs take in such portions
only as their immediate ancestors would have inherited if living.
     6.-3. When the owner of land dies without lawful issue, leaving
parents, it is the rule in some of the states, that the inheritance shall.
ascend to them, first to the father, and then to the mother, or jointly to
both, under certain regulations prescribed by statute.
     7.-4. When the intestate dies without issue or parents, the estate
descends to his brothers and sisters and their representatives. When there
are such relations, and all of equal degree of consanguinity to the
intestate, the inheritance descends to them in equal parts, however remote
from the intestate the common degree of consanguinity may be. When all the
heirs are brothers and sisters, or all of them nephews and nieces, they take
equally. When some are dead who leave issue, and some are living, then those
who are living take the share they would have taken if all had been living,
and the descendants of those who are dead inherit only the share which their
immediate parents would have received if living. When the direct lineal
descendants stand in equal degrees, they take per capita, by the head, each
one full share; when, on the contrary, they stand in different degrees of
consanguinity to the common ancestor, they take per stirpes, by roots, by
right of representation. It is nearly a general rule, that the ascending
line, after parents, is postponed to the collateral line of brothers and
sisters. Considerable difference exists in the laws of the several states,
when the next of kin are nephews and nieces, and uncles and aunts claim as
standing in the same degree. In many of the states, all these relations take
equally as being next of kin; this is the rule in the states of New
Hampshire, Vermont, (subject to the claim of the males to a double portion
as above stated,) Rhode Island, North Carolina, and Louisiana. In Alabama,
Connecticut, Delaware, Georgia, Indiana, Illinois, Kentucky, Maine,
Maryland, Massachusetts, Mississippi, Missouri, New Jersey, New York, Ohio,
Pennsylvania, South Carolina, Tennessee, and Virginia, on the contrary,
nephews and nieces take in exclusion of uncles and aunts, though they be of
equal degree of consanguinity to the intestate. In Alabama, Connecticut,
Georgia, Maryland, New Hampshire, Ohio, Rhode Island, and Vermont, there is
no representation among collaterals after the children of brothers and
sisters in Delaware, none after the grandchildren. of brothers and sisters.
In Louisiana, the ascending line must be exhausted before the estate passes
to collaterals, Code, art. 910. In North Carolina, claimants take per
stirpes in every case, though they stand in equal degree of consanguinity to
the common ancestor. As to the distinction between whole and half blood,
vide Half blood.
     8.-5. Chancellor Kent lays it down as a general rule in the American
law of descent, that when the intestate has left no lineal descendants, nor
parents, nor brothers, nor sisters, or their descendants, that the
grandfather takes the estate, before uncles and aunts, as being nearest of
kin to the intestate.
     9.-6. When the intestate dies leaving no lineal descendants, nor
parents, nor brothers, nor sisters, nor any of their descendants, nor grand
parents, as a general rule, it is presumed, the inheritance descends to the
brothers and sisters, of both the intestate's parents, and to their
descendants, equally. When they all stand in equal degree to the intestate,
they take per capita, and when in unequal degree, per stirpes. To this
general rule, however, there are slight variations in some of the states,
as, in Now York, grand parents do not take before collaterals.
    10.-7. When the inheritance came to the intestate on the part of the
father, then the brothers and sisters of the father and their descendant's
shall have the preference, and, in default of them, the estate shall descend
to the brothers and sisters of the mother, and their descendants and where
the inheritance comes to the intestate on the part of his mother, then her
brothers and sisters, and their descendants, have a preference, and in
default of them, the brothers and sisters on the side of the father, and
their descendants, inherit. This is the rule in Connecticut, New Jersey, New
York, North Carolina, Ohio, Rhode island, Tennessee, and Virginia. In
Pennsylvania, it is provided by act of assembly, April 8, 1833, that no
person who is not of the blood of the ancestors or other relations from whom
any real estate descended, or by whom it was given or devised to the
intestate, shall in any of the cases before mentioned, take any estate of
inheritance therein, but such real estate subject to such life estate as may
be in existence by virtue of this act, shall pass to and vest in such other
persons as would be entitled by this act, if the persons not of the blood of
such ancestor, or other relation, had never existed, or were dead at the
decease of the intestate. In some of the states there is perhaps no
distinction as to the descent, whether they have been acquired by purchase
or by descent from an ancestor.
    11.-8. When there is a failure of heirs under the preceding rules, the
inheritance descends" to the remaining next of kin of the intestate,
according to the rules in the statute of distribution of the personal
estate, subject to the doctrine in the preceding rules in the different
states as to the half blood, to ancestral estates, and as to the equality of
distribution. This rule prevails in several states, subject to some
peculiarities in the local laws of descent, which extend to this rule.
    12. It is proper before closing this article, to remind the reader, that
in computing the degrees of consanguinity, the civil law is followed
generally in this country, except in North Carolina, where the rules of the
common law in their application to descents are adopted, to ascertain the
degree of consanguinity. Vide the articles Branch; Consanguinity; Degree;
Line.