Synonyms for Busy:

adj.

active (adjective)
enterprising, hectic, energetic, sprightly, dynamic, active, industrious, vivacious, lively, animated, eager, stirring, sedulous, moving, tireless, bustling, assiduous, spirited.
active, on the go (adjective)
bustling, tireless, lively, full, fussy, hectic, energetic.
all (adjective)
fussy.
engaged, at work (adjective)
engaged, employed, working, occupied, unavailable, Hustling, tied up, industrious, assiduous, active.
hardworking (adjective)
industrious.
nosy, impertinent (adjective)
meddlesome, meddling, interfering, intrusive, forward, obtrusive, stirring, officious, snoopy, pushy, prying, curious.
working (adjective)
employed.

n.

hard at it, knee-deep, immersed in something, rushed/run off your feet, load down, rushed. dense, employed, congested, cramped, bulging, full, Rented, jammed, unavailable, teeming, packed, available. congestion, elaborate, bumper-to-bumper, cluttered, bottleneck, filter, congestion charge, gridlock, ornate, jam, hold up, back up. bejeweled, bedecked, embossed, decorative, delicately, Emblazoned, delicate, chintzy, beaded, action. crowded, dial, cut off, call back, call up, caller, simple, busy signal, call, answer, call-in. employ. busy (noun)
fussy, overbusy, laboring, occupy, tied up, labouring, in use, intrusive, engaged, up to, active, drudging, occupied, busybodied, fancy, meddling, interfering, officious, at work, toiling, meddlesome.
officious (noun)
curious, snoopy, pushy, nosy, obtrusive, prying, forward.

v.

social (verb)
occupy.

Other synonyms:

decorative, congestion charge, congested, teeming, bumper-to-bumper, bedecked, embossed, busy signal, gridlock, bejeweled, cluttered, Emblazoned, packed, load down, Hustling, bulging, bottleneck, rushed. hold up, jam, beaded, congestion. delicately, chintzy, dial, call back, caller. employ, crowded. delicate, call-in, dense. filter, call up. back up, cut off, full. call. thronged
jammed.
Other relevant words:
forward, bumper-to-bumper, fussy, tied up, snoopy, crowded, overbusy, occupied, cluttered, intrusive, caller, toiling, Hustling, meddling, in use, labouring, working, call, rushed, up to, jammed, drudging, ornate, obtrusive, fancy, at work, prying, congestion, hold up, involved, pushy, engaged, occupy, employ, laboring, unavailable, elaborate, hectic, gridlock, hard at it, employed, bulging, interfering, busybodied, teeming, curious, full, delicate, chintzy, nosy, beaded, officious, congested, meddlesome, bejeweled.

Usage examples for busy

  1. She is busy just now. – King Arthur's Socks and Other Village Plays by Floyd Dell
  2. However, if you are too busy – The Grey Cloak by Harold MacGrath
  3. I expect you are very busy I hope you are. – The Captives by Hugh Walpole