1 Syllable
back, black, clack, crack, flak, hack, jack, knack, lack, lakh, mac, pack, quack, rack, sac, sack, slack, smack, snack, stack, tack, thwack, track, whack, wrack
2 Syllables
aback, ack-ack, alack, attack, backtrack, bootblack, bootjack, bushwhack, claque, cutback, drawback, feedback, flapjack, flashback, greenback, gripsack, hardtack, hayrack, haystack, hijack, holdback, humpback, kickback, knapsack, plaque, prepack, set-back, setback, shellac, shellback, shoeblack, skipjack, slapjack, sumach, switchback, unpack, woolsack
3 Syllables
almanac, applejack, bareback, bric-a-brac, cardiac, haversack, horseback, ipecac, lumberjack, natterjack, pickaback, quarterback, saddleback, sidetrack, steeplejack, stickleback, supplejack, wisecrack, yellowback, zodiac
4 Syllables
ammoniac, bivouac, counterattack, demoniac
5 Syllables
aphrodisiac, dipsomaniac, hypochondriac, paradisiac