The Collaborative International Dictionary of English v.0.48:

Develop \De*vel"op\ (d[-e]*v[e^]l"[o^]p), v. t. [imp. & p. p.
   Developed; p. pr. & vb. n. Developing.] [F. d['e]veloper;
   d['e]- (L. dis-) + OF. voluper, voleper, to envelop, perh.
   from L. volup agreeably, delightfully, and hence orig., to
   make agreeable or comfortable by enveloping, to keep snug
   (cf. Voluptuous); or. perh. fr. a derivative of volvere,
   volutum, to roll (cf. Devolve). Cf. Envelop.] [Written
   also develope.]
   1. To free from that which infolds or envelops; to unfold; to
      lay open by degrees or in detail; to make visible or
      known; to disclose; to produce or give forth; as, to
      develop theories; a motor that develops 100 horse power.
      [1913 Webster]

            These serve to develop its tenets.    --Milner.
      [1913 Webster]

            The 20th was spent in strengthening our position and
            developing the line of the enemy.     --The Century.
      [1913 Webster]

   2. To unfold gradually, as a flower from a bud; hence, to
      bring through a succession of states or stages, each of
      which is preparatory to the next; to form or expand by a
      process of growth; to cause to change gradually from an
      embryo, or a lower state, to a higher state or form of
      being; as, sunshine and rain develop the bud into a
      flower; to develop the mind.
      [1913 Webster]

            The sound developed itself into a real compound.
                                                  --J. Peile.
      [1913 Webster]

            All insects . . . acquire the jointed legs before
            the wings are fully developed.        --Owen.
      [1913 Webster]

   3. To advance; to further; to prefect; to make to increase;
      to promote the growth of.
      [1913 Webster]

            We must develop our own resources to the utmost.
                                                  --Jowett
                                                  (Thucyd).
      [1913 Webster]

   4. (Math.) To change the form of, as of an algebraic
      expression, by executing certain indicated operations
      without changing the value.
      [1913 Webster]

   5. (Photog.) To cause to become visible, as an invisible or
      latent image upon plate, by submitting it to chemical
      agents; to bring to view.
      [1913 Webster]

   To develop a curved surface on a plane (Geom.), to produce
      on the plane an equivalent surface, as if by rolling the
      curved surface so that all parts shall successively touch
      the plane.

   Syn: To uncover; unfold; evolve; promote; project; lay open;
        disclose; exhibit; unravel; disentangle.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Develop \De*vel"op\, v. i.
   1. To go through a process of natural evolution or growth, by
      successive changes from a less perfect to a more perfect
      or more highly organized state; to advance from a simpler
      form of existence to one more complex either in structure
      or function; as, a blossom develops from a bud; the seed
      develops into a plant; the embryo develops into a
      well-formed animal; the mind develops year by year.
      [1913 Webster]

            Nor poets enough to understand
            That life develops from within.       --Mrs.
                                                  Browning.
      [1913 Webster]

   2. To become apparent gradually; as, a picture on sensitive
      paper develops on the application of heat; the plans of
      the conspirators develop.
      [1913 Webster]

WordNet (r) 3.0 (2006):

develop
    v 1: make something new, such as a product or a mental or
         artistic creation; "Her company developed a new kind of
         building material that withstands all kinds of weather";
         "They developed a new technique"
    2: work out; "We have developed a new theory of evolution" [syn:
       evolve, germinate, develop]
    3: gain through experience; "I acquired a strong aversion to
       television"; "Children must develop a sense of right and
       wrong"; "Dave developed leadership qualities in his new
       position"; "develop a passion for painting" [syn: develop,
       acquire, evolve]
    4: come to have or undergo a change of (physical features and
       attributes); "He grew a beard"; "The patient developed
       abdominal pains"; "I got funny spots all over my body";
       "Well-developed breasts" [syn: grow, develop, produce,
       get, acquire]
    5: come into existence; take on form or shape; "A new religious
       movement originated in that country"; "a love that sprang up
       from friendship"; "the idea for the book grew out of a short
       story"; "An interesting phenomenon uprose" [syn: originate,
       arise, rise, develop, uprise, spring up, grow]
    6: change the use of and make available or usable; "develop
       land"; "The country developed its natural resources"; "The
       remote areas of the country were gradually built up" [syn:
       build up, develop]
    7: elaborate, as of theories and hypotheses; "Could you develop
       the ideas in your thesis" [syn: explicate, formulate,
       develop]
    8: create by training and teaching; "The old master is training
       world-class violinists"; "we develop the leaders for the
       future" [syn: train, develop, prepare, educate]
    9: be gradually disclosed or unfolded; become manifest; "The
       plot developed slowly";
    10: grow, progress, unfold, or evolve through a process of
        evolution, natural growth, differentiation, or a conducive
        environment; "A flower developed on the branch"; "The
        country developed into a mighty superpower"; "The embryo
        develops into a fetus"; "This situation has developed over a
        long time"
    11: become technologically advanced; "Many countries in Asia are
        now developing at a very fast pace"; "Viet Nam is
        modernizing rapidly" [syn: modernize, modernise,
        develop]
    12: cause to grow and differentiate in ways conforming to its
        natural development; "The perfect climate here develops the
        grain"; "He developed a new kind of apple" [syn: develop,
        make grow]
    13: generate gradually; "We must develop more potential
        customers"; "develop a market for the new mobile phone"
    14: grow emotionally or mature; "The child developed beautifully
        in her new kindergarten"; "When he spent a summer at camp,
        the boy grew noticeably and no longer showed some of his old
        adolescent behavior" [syn: develop, grow]
    15: make visible by means of chemical solutions; "Please develop
        this roll of film for me"
    16: superimpose a three-dimensional surface on a plane without
        stretching, in geometry
    17: move one's pieces into strategically more advantageous
        positions; "Spassky developed quickly"
    18: move into a strategically more advantageous position;
        "develop the rook"
    19: elaborate by the unfolding of a musical idea and by the
        working out of the rhythmic and harmonic changes in the
        theme; "develop the melody and change the key"
    20: happen; "Report the news as it develops"; "These political
        movements recrudesce from time to time" [syn: break,
        recrudesce, develop]
    21: expand in the form of a series; "Develop the function in the
        following form"

Moby Thesaurus II by Grady Ward, 1.0:

336 Moby Thesaurus words for "develop":
   accrue, accumulate, achieve, acquire, actualize, add to, advance,
   affect, age, aggrandize, ameliorate, amend, amplify, appear,
   appreciate, apprentice, arise, attain, attain majority, attend,
   augment, balloon, bare, bear fruit, beautify, become of, befall,
   beget, begin, betide, betoken, bloat, bloom, blossom, blow up,
   blueprint, boom, brandish, break, break in, break the seal,
   breathe, breed, brew, bring forth, bring forward, bring into being,
   bring into view, bring out, bring to light, bring to notice,
   bring up, broaden, build, build up, bulk, bulk out, burgeon,
   call into being, chance, coin, come, come about, come along,
   come forth, come of, come of age, come on, come out, come to light,
   come to maturity, commence, complete, conceive, concoct, condition,
   contrive, cook up, crescendo, crown, culminate, cultivate, dangle,
   demonstrate, descant, design, detail, devise, dilate, discipline,
   disclose, discover, dismask, display, distend, divulge,
   do to perfection, dramatize, draw the veil, dream up, drill,
   elaborate, embellish, embody, emerge, enact, end, engender,
   enlarge, enlarge upon, ensue, establish, eventuate, evidence,
   evince, evolute, evolve, exercise, exhibit, expand, expatiate,
   explicate, exploit, expose, expose to view, express, extend,
   fabricate, fall out, fare, fetch up, fill out, finish, fit, flaunt,
   fledge, flourish, flower, follow, form, foster, frame, gain,
   gain ground, gain strength, gather, generate, germinate, get,
   get ahead, get along, give being to, give rise to, give sign,
   give token, go ahead, go forward, go up, graduate, greaten, groom,
   grow, grow better, grow up, happen, hatch, highlight, hike,
   hike up, house-train, housebreak, huff, hypertrophy, illuminate,
   impart, improve, improvise, incarnate, increase, indicate, inflate,
   intensify, invent, issue, lay bare, lay open, leave the nest,
   let daylight in, let out, lick into shape, look up, magnify,
   make clear, make do with, make headway, make plain, make progress,
   make strides, make up, manifest, materialize, maturate, mature,
   mean, meliorate, mellow, mend, mint, mount, multiply, mushroom,
   nurse, nurture, obtain, occur, open, open up, originate, outgrow,
   overdevelop, overgrow, overtop, pan out, parade, particularize,
   perfect, perform, perk up, pick up, plan, polish, practice,
   prepare, present, print, process, procreate, produce, progress,
   proliferate, promote, prosper, prove, prove to be, puff, puff up,
   pullulate, pump, pump up, put in tune, put to school, raise,
   raise the curtain, rarefy, reach, reach manhood, reach twenty-one,
   reach voting age, ready, realize, rear, refine, rehearse,
   rehearse in extenso, relate at large, represent, reproduce, result,
   reveal, ripen, rise, roll out, run up, season, send to school,
   set forth, settle down, shape up, shoot up, show, show forth,
   show improvement, show up, skyrocket, snowball, spawn, spotlight,
   spread, spring up, sprout, sprout up, strengthen, stretch,
   strike out, strip bare, sufflate, swell, take in hand, take off,
   temper, terminate, think out, think up, thrive, toga virilis,
   token, tower, train, transpire, trot out, tumefy, turn out,
   uncloak, uncover, undrape, unfold, unfurl, unkennel, unmask,
   unpack, unroll, unscreen, unsheathe, unshroud, unveil, unwrap, up,
   upshoot, upspear, upspring, upsprout, vegetate, wave, wax, widen,
   work out