2 syllables:
-meter, -metre, -seater, beater, beat her, beter, bleater, cheater, cretor, deater, deeter, detre, dieter, eater, eat her, feater, fetor, fleeter, foetor, freeter, geeter, greeter, greet her, heater, heeter, jeeter, jeter, keator, keeter, keiter, keytar, liter, litre, meeter, meet her, meter, metre, mitter, neater, peeter, peter, pieter, pleater, praeter, praeter-, praetor, preter, preter-, pretor, rieter, saeter, schleeter, seater, sheeter, skeeter, sleeter, sliter, spitir, streater, streator, streeter, strieter, sweeter, teater, teeter, teter, treater, treat her, tweeter, vietor, yeater, zetor

3 syllables:
aliter, all-seater, ammeter, ant-eater, arreter, bee-eater, beefeater, bee eater, bhangmeter, blue peter, browbeater, champetre, coal-meter, competere, completar, completer, complete her, crabeater, croweater, defeater, demeter, demetre, depleter, discreeter, drumbeater, e-meter, egg-beater, eggbeater, elfmeter, entreater, figeater, fire-eater, fisheater, fluxmeter, gas heater, gas meter, gnateater, gold-beater, goldbeater, leadbeater, light meter, luxmeter, maltreater, man-eater, maneater, meateater, molitor, oil heater, oometer, physeter, preheater, propraetor, propretor, pyoureter, rainmeter, receiptor, reheater, repeater, retreater, rug beater, saint peter, saltpetre, seedeater, sin-eater, snow eater, space heater, square meter, st peter, tenthmetre, toad-eater, toadeater, torquemeter, two-seater, ureter, vanmeter, vanmetre, wattmeter, wife-beater, windcheater, world-beater, worldbeater

4 syllables:
aerometer, amperemeter, antimeter, attolitre, attometre, avometer, barkometer, bathymeter, bolometer, brontometer, calcimeter, campimeter, carpet beater, centiliter, centilitre, centimeter, centimetre, chlorometer, clinometer, common meter, coulometer, cryometer, cubic meter, cyclometer, dasymeter, decametre, deciliter, decilitre, decimeter, decimetre, decremeter, dekametre, densimeter, diametre, dosemeter, ergometer, exalitre, exametre, expositor, fathometer, femtometre, fluorimeter, focimeter, gasometer, gigalitre, gigameter, gigametre, gravimeter, halometer, hannah jeter, hazemeter, hectolitre, hectometre, holometer, honey-eater, honeyeater, honey eater, hypermeter, joulemeter, kilolitre, kilometer, kilometre, klinometer, konimeter, labimeter, lanameter, logometer, lotos-eater, lotus-eater, lotus eater, macrometer, manometer, megameter, megametre, mekometer, mentimeter, micrometre, mililiter, milliammeter, milliliter, millilitre, millimeter, millimetre, milometer, multimeter, nanolitre, nanometer, nanometre, neotheater, newton-meter, newton-metre, nilometer, nonsecretor, oenometer, ohmmeter, overeater, oximeter, pachymeter, pantometer, passometer, pelvimeter, petalitre, petameter, petametre, phall-o-meter, picolitre, picometre, planimeter, planometer, platymeter, plessimeter, pleximeter, postage meter, pulsimeter, pulsometer, qualimeter, salimeter, salometer, sillometer, similiter, solar heater, sonometer, stadimeter, stenometer, sulfameter, superheater, tachymeter, tasimeter, taximeter, telemeter, tensimeter, teralitre, terameter, terametre, tetrameter, tonometer, trick-or-treater, turgometer, vacuometer, vinometer, voltameter, water heater, water meter, yoctolitre, yoctometre, yottalitre, yottameter, yottametre, zentimeter, zeptolitre, zeptometre, zettalitre, zettameter, zettametre

5 syllables:
acetimeter, acidimeter, actinometer, alcalimeter, algesimeter, anthropometer, auxanometer, cephalometer, co-oximeter, coercimeter, cyanometer, ductilimeter, elastometer, electric heater, exposure meter, extensimeter, galvanometer, geodimeter, globulimeter, gram-centimeter, gravity meter, indigometer, intoximeter, kerosene heater, kilogram-meter, kilogrammetre, microammeter, myrialitre, myriameter, myriametre, opacimeter, opium-eater, penetrameter, photogrammeter, pluviameter, pneumonometer, profilometer, pyranometer, scintillometer, stereometer, submillimeter, transmissometer, turbidimeter, ureameter, velocimeter, viscosimeter

6 syllables:
albuminimeter, alcoholometer, baromacrometer, carmelita jeter, cubic centimeter, cubic millimeter, dynactinometer, haematinometer, haemomanometer, lactodensimeter, microbolometer, micromillimeter, micromillimetre, spectrofluorimeter, sphygmomanometer, thermogravimeter

7 syllables:
psychogalvanometer

3 syllables:
madrepore, bandleader

4 syllables:
dekaliter