1 syllable:
at, bat, batt, brat, cat, chat, dat, fat, flat, gat, gatt, gnat, hat, kat, mat, matt, matte, nat, pat, platt, platte, pratt, rat, sat, scat, slat, spat, splat, sprat, stat, tat, that, vat

2 syllables:
and that, arhat, at-bat, backchat, bad hat, bath mat, bearcat, bear cat, begat, big cat, black cat, black rat, blue cat, bobcat, bogmat, bone fat, brass hat, brickbat, brown bat, brown rat, bullbat, but that, buy at, call at, cave bat, chip at, chitchat, cocked hat, combat, coon cat, d'etat, diktat, dingbat, does that, doormat, down pat, dress hat, ducat, eat at, eclat, expat, fall flat, felt hat, format, fruit bat, fur hat, gall gnat, get at, gnaw at, hard hat, hazmat, hellcat, hepat, high hat, house cat, in that, is that, jest at, kismat, landsat, langsat, laugh at, leaf fat, look at, manx cat, mole rat, mudcat, mud flat, mule fat, muskrat, nonfat, north platte, numbat, of that, on that, packrat, pack rat, palm cat, peck at, pick at, pith hat, place mat, play at, pluck at, plug hat, poke at, polecat, prayer mat, pull at, quail at, rat-tat, red bat, rice rat, roof rat, sabbat, sadat, sand cat, sand rat, sea mat, shine at, shop at, silk hat, slouch hat, snap at, sno-cat, south platte, standpat, stand pat, stay at, straw hat, such that, thereat, tin hat, tomcat, top hat, to that, trade rat, true cat, wharf rat, whereat, wildcat, wing flat, wink at, with that, wombat, wood rat, wool fat, work at

3 syllables:
achromat, acrobat, aegrotat, alley cat, arrive at, assignat, autocrat, automat, a look at, baseball bat, beaver rat, become flat, bell the cat, big brown bat, bishop's hat, bowler hat, bridle at, bristle at, bureaucrat, burmese cat, butterfat, campaign hat, caveat, channel cat, civet cat, connive at, copycat, cotton rat, coup d'etat, cowboy hat, cricket bat, cryostat, dabble at, democrat, desert rat, diplomat, excel at, firebrat, fisher cat, flying cat, frosted bat, fungistat, fungus gnat, guano bat, gujarat, gujerat, habitat, haemostat, hemostat, hognose bat, horseshoe bat, jackass bat, jungle cat, kitty-cat, laundromat, leopard cat, looking at, maltese cat, marrowfat, marten cat, mastiff bat, megabat, microbat, miner's cat, native cat, new world chat, nitrostat, norway rat, old world chat, opera hat, orange bat, pallas's cat, pallid bat, panipat, panther cat, persian cat, photostat, picture hat, pit-a-pat, pitapat, pitty-pat, plutocrat, pocket rat, pussycat, pyrostat, railroad flat, reformat, safety hat, sewer rat, shovel hat, spotted bat, tabby cat, table mat, technocrat, theocrat, thermostat, tiger cat, tit for tat, under that, valued at, vampire bat, water mat, water rat, welcome mat, what does that, woman's hat, wrestling mat, ziggurat

4 syllables:
amadavat, angora cat, animal fat, aristocrat, avadavat, blue channel cat, buffalo gnat, calico cat, cavalier hat, chinchilla rat, chip away at, coelostat, data format, domestic cat, dwarf pocket rat, edible fat, egyptian cat, false vampire bat, humidistat, kangaroo rat, little brown bat, magnificat, mexican hat, monochromat, naked mole rat, opossum rat, physiocrat, pocketed bat, rat-a-tat-tat, siamese cat, tortoiseshell-cat, true vampire bat

5 syllables:
bacteriostat, carnivorous bat, commissariat, madagascar cat, male aristocrat, marsupial rat, microhabitat, orange horseshoe bat, ord kangaroo rat

6 syllables:
european brown bat, european wildcat, female aristocrat, florida water rat

3 syllables:
neuroblast