The Collaborative International Dictionary of English v.0.48:

Creep \Creep\ (kr[=e]p), v. t. [imp. Crept (kr[e^]pt) (Crope
   (kr[=o]p), Obs.); p. p. Crept; p. pr. & vb. n. Creeping.]
   [OE. crepen, creopen, AS. cre['o]pan; akin to D. kruipen, G.
   kriechen, Icel. krjupa, Sw. krypa, Dan. krybe. Cf. Cripple,
   Crouch.]
   1. To move along the ground, or on any other surface, on the
      belly, as a worm or reptile; to move as a child on the
      hands and knees; to crawl.
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            Ye that walk
            The earth, and stately tread, or lowly creep.
                                                  --Milton.
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   2. To move slowly, feebly, or timorously, as from
      unwillingness, fear, or weakness.
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            The whining schoolboy . . . creeping, like snail,
            Unwillingly to school.                --Shak.
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            Like a guilty thing, I creep.         --Tennyson.
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   3. To move in a stealthy or secret manner; to move
      imperceptibly or clandestinely; to steal in; to insinuate
      itself or one's self; as, age creeps upon us.
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            The sophistry which creeps into most of the books of
            argument.                             --Locke.
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            Of this sort are they which creep into houses, and
            lead captive silly women.             --2. Tim. iii.
                                                  6.
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   4. To slip, or to become slightly displaced; as, the
      collodion on a negative, or a coat of varnish, may creep
      in drying; the quicksilver on a mirror may creep.
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   5. To move or behave with servility or exaggerated humility;
      to fawn; as, a creeping sycophant.
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            To come as humbly as they used to creep. --Shak.
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   6. To grow, as a vine, clinging to the ground or to some
      other support by means of roots or rootlets, or by
      tendrils, along its length. "Creeping vines." --Dryden.
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   7. To have a sensation as of insects creeping on the skin of
      the body; to crawl; as, the sight made my flesh creep. See
      Crawl, v. i., 4.
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   8. To drag in deep water with creepers, as for recovering a
      submarine cable.
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The Collaborative International Dictionary of English v.0.48:

Creep \Creep\, n.
   1. The act or process of creeping.
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   2. A distressing sensation, or sound, like that occasioned by
      the creeping of insects.
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            A creep of undefinable horror.        --Blackwood's
                                                  Mag.
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            Out of the stillness, with gathering creep,
            Like rising wind in leaves.           --Lowell.
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   3. (Mining) A slow rising of the floor of a gallery,
      occasioned by the pressure of incumbent strata upon the
      pillars or sides; a gradual movement of mining ground.
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WordNet (r) 3.0 (2006):

creep
    n 1: someone unpleasantly strange or eccentric [syn: creep,
         weirdo, weirdie, weirdy, spook]
    2: a slow longitudinal movement or deformation
    3: a pen that is fenced so that young animals can enter but
       adults cannot
    4: a slow mode of locomotion on hands and knees or dragging the
       body; "a crawl was all that the injured man could manage";
       "the traffic moved at a creep" [syn: crawl, crawling,
       creep, creeping]
    v 1: move slowly; in the case of people or animals with the body
         near the ground; "The crocodile was crawling along the
         riverbed" [syn: crawl, creep]
    2: to go stealthily or furtively; "..stead of sneaking around
       spying on the neighbor's house" [syn: sneak, mouse,
       creep, pussyfoot]
    3: grow or spread, often in such a way as to cover (a surface);
       "ivy crept over the walls of the university buildings"
    4: show submission or fear [syn: fawn, crawl, creep,
       cringe, cower, grovel]

Moby Thesaurus II by Grady Ward, 1.0:

138 Moby Thesaurus words for "creep":
   SOB, all fours, amble, andante, bastard, bend the knee, bootlick,
   bow, bow and scrape, bugger, claudicate, claudication, couch,
   cower, crawl, crawling, creeping, cringe, crouch, dead march,
   dogtrot, drag, drag along, drag on, drag out, fart, fawn,
   feel creepy, feel funny, flatter, footpace, funeral march,
   go dead slow, go on, go on tiptoe, go slow, grovel, gumshoe,
   gumshoeing, have gooseflesh, have the creeps, heel, hobble, hood,
   hooligan, idle, inch, inch along, jerk, jog, jog trot, jog-trot,
   kneel, kowtow, lay wait, laze, leisurely gait, lick the dust,
   lickspittle, lie in wait, limp, linger, linger on, louse,
   lumbering pace, lurk, meanie, mincing steps, mosey, mother,
   nightwalk, nightwalking, pad, padding, pill, plod, poke,
   poke along, prowl, prowling, pussyfoot, pussyfooting, rack, rat,
   saunter, scrabble, scramble, shadow, shamble, shit, shithead,
   shitheel, shuffle, shuffle along, sidle, sidling, skulk, slink,
   slinking, slither, slouch, slow march, slow motion, snake, snaking,
   sneak, sneaking, squirm, stagger along, stalk, steal, steal along,
   stealing, stinkard, stinker, stoop, stroll, tarry, tippytoe,
   tiptoe, tiptoeing, toadeat, toady, toddle, toddle along,
   totter along, traipse, truckle, trudge, turd, waddle, walk,
   wear on, wiggle, worm, worm along, worming, wriggle



The Jargon File (version 4.4.7, 29 Dec 2003):

creep
 v.

    To advance, grow, or multiply inexorably. In hackish usage this verb has
    overtones of menace and silliness, evoking the creeping horrors of
    low-budget monster movies.