2 syllables:
appar, apper, capper, chapar, clapper, crapper, dapper, flapper, frapper, gapper, happer, hapur, japer, japper, kapper, kapur, klapper, knapper, lapar, laper, lapper, mapper, napper, papper, rapper, sapper, schnapper, scrapper, slapper, slap her, snapper, strapper, tapper, trapper, whapper, wrapper, wrap her, yapper, zapper

3 syllables:
attraper, backslapper, bishapur, catnapper, didapper, dimapur, divedapper, dognapper, dust wrapper, empapar, gray snapper, hog snapper, kidnaper, kidnapper, knee-slapper, kolhapur, portmapper, ranakpur, recapper, red snapper, thigh-slapper, uncapper, wit-snapper

4 syllables:
chance the rapper, citymapper, handicapper, mangrove snapper, megan tapper, mutton snapper, spirit rapper, understrapper, whippersnapper, wiretapper

6 syllables:
alligator snapper

2 syllables:
adder, attar, backer, bader, bagger, bakker, batter, blabber, bladder, catarrh, chatter, clabber, clatter, cracker, dagger, faqir, flatter, grabber, hacker, hatter, jabber, jaeger, jagger, knacker, lacquer, ladder, latter, madder, mater, matter, nagger, natter, pabir, packer, patter, platter, ratter, satyr, scatter, shatter, slabber, slacker, smacker, smatter, spatter, splatter, stabber, stagger, swagger, tatar, tatter, tracker, whacker

3 syllables:
air bladder, attacker, backscatter, back matter, bespatter, cat cracker, death adder, end matter, fish ladder, front matter, gray matter, grey matter, jack ladder, line backer, milk adder, no matter, puff adder, puff batter, rope ladder, sea ladder, step ladder, swim bladder, the matter, vannatter, waste matter, white madder, white matter, wild madder

4 syllables:
banded adder, cannon cracker, checkered adder, cloak-and-dagger, double dagger, fecal matter, flaccid bladder, fritter batter, graham cracker, jacob's ladder, mongol tatar, monkey ladder, oyster cracker, pancake batter, pilot ladder, pitter-patter, scaling ladder, soda cracker, spanish dagger, spin the platter, state of matter, subject matter, turko-tatar, written matter

5 syllables:
aerial ladder, crux of the matter, extension ladder, indian madder, textual matter

6 syllables:
catalytic cracker, northern jacob's ladder, pictorial matter, urinary bladder

7 syllables:
accommodation ladder, conservation of matter

9 syllables:
law of conservation of matter