1.  back up(v = verb.social) support - give moral or psychological support, aid, or courage to; "She supported him during the illness"; "Her children always backed her up"
Derived form noun backup₅
Sample sentences: Sam cannot back up Sue

2.  back up(v = verb.motion) back down, back off - move backwards from a certain position; "The bully had to back down"
is one way to draw back, move back, pull away, pull back, recede, retire, retreat, withdraw
Sample sentences: Something ----s; Somebody ----s

3.  back up(v = verb.change) back - establish as valid or genuine; "Can you back up your claims?"
is one way to affirm, confirm, corroborate, substantiate, support, sustain
Sample sentences: Somebody ----s something; Something ----s something

4.  back up(v = verb.creation) - make a copy of (a computer file) especially for storage in another place as a security copy; "You'd better back up these files!"
is one way to copy, re-create
Derived form noun backup₄
Sample sentences: Somebody ----s something

5.  back up(v = verb.contact) choke, choke off, clog, clog up, congest, foul - become or cause to become obstructed; "The leaves clog our drains in the Fall"; "The water pipe is backed up"
is one way to block, close up, impede, jam, obstruct, obturate, occlude
Derived form noun backup₁
Sample sentences: Something ----s; Somebody ----s something; Something ----s something

1.  to move in a reverse direction; -- used of vehicles or animals. [PJC]

2.  to accumulate due to a blockage of flow; as, a traffic backup due to an accident; a sewage backup. [PJC]

1.  to serve as a backup{3} for (another person or persons); as, the patrolmen backed up the detectives as they went inside to make the arrest; the center fielder backed up the shortstop on the play. [PJC]

2.  to make a backup{5} of; as, the sysop backed up the purchasing data files every night. [PJC]

VB  aid, assist, help, succor, lend one's aid, come to the aid, of, contribute, subscribe to, bring aid, give aid, furnish aid, afford aid, supply aid, give a helping hand, stretch a hand, lend a helping hand, lend a hand, bear a helping hand, hold out a hand, hold out a helping hand, give one a life, give one a cast, give one a turn, take by the hand, take in tow, help a lame dog over a stile, lend wings to, relieve, rescue, set up, set agoing, set on one's legs, bear through, pull through, give new life to, be the making of, reinforce, reenforce, recruit, set forward, put forward, push forward, give a lift, give a shove, give an impulse to, promote, further, forward, advance expedite, speed, quicken, hasten, support, sustain, uphold, prop, hold up, bolster, cradle, nourish, nurture, nurse, dry nurse, suckle, put out to nurse, manure, cultivate, force, foster, cherish, foment, feed the flame, fan the flame, serve, do service to, tender to, pander to, administer to, subminister to, minister to, tend, attend, wait on, take care of, entertain, smooth the bed of death, oblige, accommodate, consult the wishes of, humor, cheer, encourage, second, stand by, back, back up, pay the piper, abet, work for, make interest for, stick up for, take up the cudgels for, take up the cause of, espouse the cause of, adopt the cause of, advocate, beat up for recruits, press into the service, squire, give moral support to, keep in countenance, countenance, patronize, lend oneself to, lend one's countenance to, smile upon, shine upon, favor, befriend, take in hand, enlist under the banners of, side with, be of use to, subserve, benefit, render a service, conduce.

VB  be supported, lie on, sit on, recline on, lean on, loll on, rest on, stand on, step on, repose on, abut on, bear on, be based on, have at one's back, bestride, bestraddle, support, bear, carry, hold, sustain, shoulder, hold up, back up, bolster up, shore up, uphold, upbear, prop, under prop, under pin, under set, riprap, bandage, give support, furnish support, afford support, supply support, lend support, give foundations, furnish foundations, afford foundations, supply foundations, lend foundations, bottom, found, base, ground, imbed, embed, maintain, keep on foot, aid.

act up, add up, answer back, ante up, back, back and fill, back and forth, back away, back brace, back breaker, back burner, back channel, back circle, back country, back door, back down, back end, back entrance, back exercise, back fire, back judge, back matter, back number, back of beyond, back off, back out, back pack, back porch, back room, back saw, back scratching, back seat, back stairs, back street, back talk, back to back, back tooth, back way, backed up, ball up, balled up, bang up, bear up, beat back, beat up, beef up, beefed up, belly up, belt up, bind up, blaze up, block up, blow up, blowing up, blown up, board up, bob up, bollix up, bollixed up, bollocks up, bolster up, bomb up, bone up, book up, boost up, botch up, bottle up, bounce back, bound up, box up, brace up, break one's back, break up, brick up, bridle up, bring back, bring up, bringing up, brisk up, bristle up, brush up, bubble up, buck up, bucked up, build up, bump up, bunch up, bundle up, buoy up, burn up, bust up, butter up, button up, buy back, buy up, call back, call up, carry back, carve up, cast up, catch up, catch up with, caught up, caught up in, ceding back, chain up, chalk up, charge up, chat up, check up on, cheer up, chew up, chin up, chirk up, chock up, choke back, choke up, choose up, chop up, chuck up the sponge, chum up, churn up, clam up, clap up, clean up, clear up, climb up, clock up, clog up, close up, cloud up, clouding up, clutter up, cobble up, cock up, come back, come back at, come up, come up against, come up to, coming back, conjure up, cook up, coop up, cork up, cotton up, cough up, coughing up, couple up, cover up, cozy up, crack up, crank up, crap up, creep up, crock up, crop up, curl up, curled up, cut back, cut up, dam up, date back, deck up, die back, dig up, digging up, dish up, divided up, divvy up, do up, doctor up, doll up, dolled up, done up, dope up, double back, double up, drag up, draw back, draw up, dream up, dredge up, dress up, dried up, drink up, drive back, drive up, drive up the wall, drop back, drum up, dry up, drying up, dummy up, earth up, ease up, eat up, edge up, end up, even up, face up, face up to, faggot up, fake up, fall back, fancied up, fancy up, fat back, fatten up, fed up, feed back, felt up, fess up, fetch up, fig up, fight back, fill up, finish up, fire up, firm up, fix up, flame up, flanker back, flare up, flash back, fluff up, fog up, fold up, follow up, follow up on, foot up, force back, fork up, fort up, foul up, frame up, freshen up, from way back, fuck up, furbish up, gang up, gang up on, gas up, gather up, gear up, get back, get back at, get up, ginger up, give back, give up, giving up, glam up, go back, go back on, go back over, go up, go up in smoke, gobble up, grow up, grown up, grub up, gum up, gummed up, gussied up, gussy up, ham it up, hang back, hang up, hard up, hark back, hash up, haul up, head up, heap up, heat up, heated up, heave up, heft up, held up, het up, high up, higher up, hike up, hit it up, hit up, hitch up, hive up, hoke up, hold back, hold up, hole up, hook up, hook up with, hop up, hopped up, hot up, hung up, hurry up, hush up, hype up, ice up, jack up, jazz up, jolly up, juice up, jump up, jumping up and down, keep back, keep up, kept up, key up, keyed up, kick back, kick up, kink up, kit up, knock back, knock up, lace up, laid up, land up, lap up, laugh it up, lay up, lead up, lean back, let up, lift up, light up, lighten up, limber up, line up, lined up, link up, live it up, live up to, liven up, load up, lock up, log up, look back, look up, look up to, looking up, loosen up, louse up, made up, make up, make up one's mind, make up to, mark up, mat up, matte up, measure up, measure up to, meet up with, mess up, messed up, mix up, mixed up, mock up, mop up, mount up, mount up to, move back, move back and forth, move up, muck up, mucked up, muddy up, muffle up, mug up, muster up, offer up, open up, own up, pal up, pass up, pat on the back, patch up, pay back, pay up, paying back, pen up, pent up, pep up, perk up, perked up, pick up, pick up the gauntlet, pile up, pin up, pipe up, play back, play up, play up to, plump up, point up, polish up, pony up, pop up, pound up, prang up, pretty up, prick up, prim up, prop up, propping up, psych up, psyched up, puff up, puffed up, pull back, pull up, pull up short, pull up stakes, pumped up, push back, push up, put back, put up, put up job, put up to, put up with, queue up, rachet up, rack up, raise up, rake up, ramp up, rear back, relation back, rev up, rig up, ring up, rip up, rise up, roll back, roll up, rope up, rough up, round up, rout up, rub up, ruck up, ruffle up, run up, runner up, running back, sack up, save up, saved up, scale up, scare up, scoop up, scrape up, scratch up, screw up, scrub up, scrunch up, seal up, sell up, send back, serve up, set back, set up, sew up, sex up, shack up, shake up, shape up, shine up, shine up to, shoot up, shore up, shoring up, show up, shown up, shrink back, shrivel up, shut up, sidle up, sign up, silt up, sink back, sit back, sit up, size up, slack up, slice up, slick up, slicked up, slide back, slip back, slip up, slow up, slurp up, smarten up, smash up, smell up, snap back, snap up, snarl up, snatch up, sneak up, soak up, soaking up, soar up, sober up, soften up, sop up, soup up, speak up, speak up for, spear up, speed up, speeded up, spice up, spiff up, spiffed up, spirit up, spit up, split up, sponge up, spring up, spruce up, spruced up, square up, stack up, stand back, stand up, stand up for, stand up to, start up, stay up, steam up, steamed up, step up, stick up, stick up for, stink up, stir up, stirred up, stop up, stopped up, stored up, straighten up, strike back, strike up, string up, stuck up, suck up, suck up to, sum up, summing up, summon up, sunny-side up, swallow up, sweep up, swell up, swept up, swoop up, swot up, take back, take up, take up arms, take up with, taken up, talk back, tart up, team up, tear up, tee up, tense up, think back, think up, throw back, throw up, thrust back, tidy up, tie up, tied up, tier up, tighten up, tog up, togged up, tone up, toss back, toss up, tot up, tote up, touch up, touch up paint, travel back and forth, trice up, trick up, trim back, trip up, true up, trump up, trumped up, tune up, turn back, turn up, turn up the heat, turn up the pressure, turned up, tying up, up, up and down, up country, up here, up in arms, up in the air, up on, up quark, up the stairs, up to, up to her neck, up to his neck, up to my neck, up to now, up to our necks, up to their necks, up to your neck, use up, used up, using up, vamp up, vomit up, wake up, waking up, wall up, warm up, wash up, washed up, water back, watteau back, well up, whip up, whomp up, whoop it up, win back, wind up, wipe up, wise up, work up, worked up, wound up, wrack up, wrap up, wrapped up, wrapped up in, write up, wrought up, yield up, zip up