The Collaborative International Dictionary of English v.0.48:

Dependent \De*pend"ent\, n.
   1. One who depends; one who is sustained by another, or who
      relies on another for financial support or favor; a
      hanger-on; a retainer; as, a numerous train of dependents.
      [1913 Webster]

            A host of dependents on the court, suborned to play
            their part as witnesses.              --Hallam.
      [1913 Webster]

   2. That which depends; corollary; consequence.
      [1913 Webster]

            With all its circumstances and dependents. --Prynne.
      [1913 Webster]

   Note: See the Note under Dependant.
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Dependent \De*pend"ent\, a. [L. dependens, -entis, p. pr.
   dependere. See Depend, and cf. Dependant.]
   1. Hanging down; as, a dependent bough or leaf.
      [1913 Webster]

   2. Relying on, or subject to, something else for support; not
      able to exist, or sustain itself, or to perform anything,
      without the will, power, or aid of something else; not
      self-sustaining; subordinate; -- often with on or upon;
      as, dependent on God; dependent upon friends. Opposite of
      independent. [Narrower terms: interdependent,
      mutualist, mutually beneficial; parasitic, parasitical,
      leechlike, bloodsucking; subordinate; underage;
      myrmecophilous; symbiotic] Also See: unfree.
      [1913 Webster]

            England, long dependent and degraded, was again a
            power of the first rank.              --Macaulay.
      [1913 Webster]

   3. conditional; contingent or conditioned. Opposite of
      unconditional.

   Syn: qualified.
        [WordNet 1.5]

   4. addicted to drugs.

   Syn: addicted, dependent, drug-addicted, hooked, strung-out.
        [WordNet 1.5]

   Dependent covenant or Dependent contract (Law), one not
      binding until some connecting stipulation is performed.

   Dependent variable (Math.), a varying quantity whose
      changes are arbitrary, but are regarded as produced by
      changes in another variable, which is called the
      independent variable.
      [1913 Webster]

WordNet (r) 3.0 (2006):

dependent
    adj 1: relying on or requiring a person or thing for support,
           supply, or what is needed; "dependent children";
           "dependent on moisture" [ant: independent]
    2: contingent on something else [syn: dependent, dependant,
       qualified]
    3: (of a clause) unable to stand alone syntactically as a
       complete sentence; "a subordinate (or dependent) clause
       functions as a noun or adjective or adverb within a sentence"
       [syn: dependent, subordinate] [ant: independent,
       main(a)]
    4: held from above; "a pendant bunch of grapes" [syn: pendent,
       pendant, dependent]
    5: being under the power or sovereignty of another or others;
       "subject peoples"; "a dependent prince" [syn: subject,
       dependent]
    6: addicted to a drug [syn: dependent, dependant, drug-
       addicted, hooked, strung-out]
    n 1: a person who relies on another person for support
         (especially financial support) [syn: dependant,
         dependent]

The Devil's Dictionary (1881-1906):

DEPENDENT, adj.  Reliant upon another's generosity for the support
which you are not in a position to exact from his fears.