The Collaborative International Dictionary of English v.0.48:

Bump \Bump\, v. i. [See Boom to roar.]
   To make a loud, heavy, or hollow noise, as the bittern; to
   boom.
   [1913 Webster]

         As a bittern bumps within a reed.        --Dryden.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bump \Bump\, n.
   The noise made by the bittern.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bump \Bump\ (b[u^]mp; 215), v. t. [imp. & p. p. Bumped
   (b[u^]mpt); p. pr. & vb. n. Bumping.] [Cf. W. pwmp round
   mass, pwmpiaw to thump, bang, and E. bum, v. i., boom to
   roar.]
   To strike, as with or against anything large or solid; to
   thump; as, to bump the head against a wall.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bump \Bump\, v. i.
   To come in violent contact with something; to thump. "Bumping
   and jumping." --Southey.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bump \Bump\, n. [From Bump to strike, to thump.]
   1. A thump; a heavy blow.
      [1913 Webster]

   2. A swelling or prominence, resulting from a bump or blow; a
      protuberance.
      [1913 Webster]

            It had upon its brow
            A bump as big as a young cockerel's stone. --Shak.
      [1913 Webster]

   3. (Phren.) One of the protuberances on the cranium which are
      associated with distinct faculties or affections of the
      mind; as, the bump of "veneration;" the bump of
      "acquisitiveness." [Colloq.]
      [1913 Webster]

   4. The act of striking the stern of the boat in advance with
      the prow of the boat following. [Eng.]
      [1913 Webster]

WordNet (r) 3.0 (2006):

bump
    n 1: a lump on the body caused by a blow
    2: something that bulges out or is protuberant or projects from
       its surroundings; "the gun in his pocket made an obvious
       bulge"; "the hump of a camel"; "he stood on the rocky
       prominence"; "the occipital protuberance was well developed";
       "the bony excrescence between its horns" [syn: bulge,
       bump, hump, swelling, gibbosity, gibbousness,
       jut, prominence, protuberance, protrusion,
       extrusion, excrescence]
    3: an impact (as from a collision); "the bump threw him off the
       bicycle" [syn: blow, bump]
    v 1: knock against with force or violence; "My car bumped into
         the tree" [syn: bump, knock]
    2: come upon, as if by accident; meet with; "We find this idea
       in Plato"; "I happened upon the most wonderful bakery not
       very far from here"; "She chanced upon an interesting book in
       the bookstore the other day" [syn: find, happen,
       chance, bump, encounter]
    3: dance erotically or dance with the pelvis thrust forward;
       "bump and grind"
    4: assign to a lower position; reduce in rank; "She was demoted
       because she always speaks up"; "He was broken down to
       Sergeant" [syn: demote, bump, relegate, break, kick
       downstairs] [ant: advance, elevate, kick upstairs,
       promote, raise, upgrade]
    5: remove or force from a position of dwelling previously
       occupied; "The new employee dislodged her by moving into her
       office space" [syn: dislodge, bump]

Moby Thesaurus II by Grady Ward, 1.0:

460 Moby Thesaurus words for "bump":
   CAT, abase, abasement, ability, aerospace, aerosphere, air hole,
   air pocket, airspace, appulse, aptness, assassinate, assault, bang,
   bang into, bear, bear upon, bearing, bent, bilge, blain, bleb,
   blister, blob, blow, bob, bobble, boil, boost, boot, boss, bounce,
   bow, break, brunt, bubble, buck, buffet, bulb, bulge, bull, bulla,
   bulldoze, bulldozing, bulling, bump against, bump into, bump off,
   bunch, bunion, bunt, burl, burst, bust, butt, butt against, button,
   cahot, caliber, can, cannon, capability, capacity, carambole,
   carbuncle, carom, carom into, cashier, casting down, ceiling,
   chance, chatter, chine, chink, chuckhole, clap, clash, click,
   clink, clop, clump, clunk, collide, collision, colophon,
   come across, come into collision, concavity, concuss, concussion,
   condyle, confront each other, convex, convexity, corn, crack,
   crack up, crack-up, cram, crash, crash into, crosswind, crowd,
   crump, crunch, cyst, dactylogram, dactylograph, dash into, debase,
   debasement, defrock, degradation, degrade, degrading, dement,
   demote, demotion, dent, deplume, depluming, depose, deprive,
   destroy, didder, dig, dilatation, dilation, dint, disbar,
   discharge, disemploy, disgrade, disgrading, dismiss, dispatch,
   displace, displume, displuming, distension, dither, do away with,
   do in, dowel, dower, downgrade, downgrading, dowry, drive,
   drum out, dull thud, ear, edema, elbow, eliminate, embossment,
   empty space, encounter, endowment, equipment, excrescence, execute,
   expel, faculty, fall foul of, falter, favorable wind, fingerprint,
   fire, flair, flange, flap, flick, flop, flump, fog, footmark,
   footprint, footstep, force, forte, fossil footprint, foul, front,
   furlough, furuncle, gall, genius, gift, give the ax, give the gate,
   gnarl, goad, grimace, hammering, handle, have an ague, head,
   head wind, high-pressure area, hill, hit, hit against, hole,
   humble, humbling, hump, hunch, hurt, hurtle, hustle, ice, ichnite,
   ichnolite, impact, impinge, impingement, impress, impression,
   imprint, indent, indentation, indention, instinct, intumescence,
   ionosphere, jab, jactitate, jam, jar, jerk, jetstream, jig, jigget,
   jiggle, jog, joggle, jolt, jostle, jounce, jump, kick,
   kick upstairs, kill, knack, knob, knock, knock against, knot, knur,
   knurl, lay off, let go, let out, light, lip, liquidate, long suit,
   loop, low-pressure area, lower, luck, lump, make redundant,
   makings, mauling, meet, meeting, metier, mole, mountain, mudhole,
   murder, natural endowment, natural gift, nevus, nub, nubbin,
   nubble, nudge, onslaught, overcast, pad, papilloma, parts, pat,
   patter, paw print, pawmark, peg, pension off, percuss, percussion,
   pile drive, pimple, pitapat, pitter-patter, plump, plunk, pock,
   pocket, poke, pop, potential, pothole, power, powers, press,
   pressure, print, prod, protuberance, pug, pugmark, punch, push,
   pustule, put away, quake, qualification, quaver, quiver, ram,
   ram down, ramming, rap, rattle, read out of, reduce, reduction,
   release, remove, replace, report, retire, rib, rictus, ridge, ring,
   rising, roughness, rub out, run, run across, run against, run into,
   rut, sack, seal, sebaceous cyst, separate forcibly, shake, shiver,
   shock, shoulder, shove, shudder, sideswipe, sigil, signet, slam,
   slam into, slap, slat, sledgehammering, smack, smack into, smash,
   smash into, smash up, smash-up, smashing, soup, space, speciality,
   spine, splat, stamp, step, stratosphere, stress, strike,
   strike against, strip, strip of rank, stripping of rank,
   strong flair, strong point, stud, stumble, style, substratosphere,
   superannuate, surplus, suspend, swap, swell, swelling, swollenness,
   tab, tail wind, talent, talents, tamp, tap, the goods, the stuff,
   thrust, thrusting, thud, thumbmark, thumbprint, thump, thwack, tic,
   tick, tinkle, tremble, tremor, tropopause, troposphere, trough,
   tubercle, tubercule, tumble, tumefaction, tumescence, tumidity,
   tumor, tunk, turbulence, turgescence, turgescency, turgidity, turn,
   turn off, turn out, twitch, twitter, unfrock, verruca, vesicle,
   vestige, vibrate, visibility, visibility zero, wale, wallop, wart,
   waste, welt, wen, whack, wham, whap, what it takes, whomp, whop,
   wipe out, wobble



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

bump
 vt.

    Synonym for increment. Has the same meaning as C's ++ operator. Used esp.
    of counter variables, pointers, and index dummies in for, while, and
    do-while loops.


The Free On-line Dictionary of Computing (30 December 2018):

bump

   Increment.  E.g. C's ++ operator.  It is used especially of
   counter variables, pointers and index dummies in "for",
   "while", and "do-while" loops.

   (1994-11-29)