3 syllables:
brontosaur, sloganeer, hosteller, monitor, hollander, godmother, nodular, polymer, proposer, jocular, cockchafer, sodbuster, popular, cocklebur, modeler, hogchoker, goddaughter, commodore, colander, columnar, oliver, blockbuster, pompadour, bolivar, gospeler, modeller, monomer, globular, onager, almoner, stomacher, gobbler, gossamer, commoner, nonpolar, pothunter, conifer, nothosaur, gossiper, slopseller, cottager, gospeller, groveller, holloware, ocular, promiser, promisor, quadrature, swashbuckler, troposphere, wobbler

4 syllables:
biographer, atmometer, picometer, spectrometer, cryometer, psychrometer, tachometer, spherometer, manometer, astronomer, algometer, hodometer, unpopular, decametre, bilocular, demographer, photographer, pornographer, binocular, clinometer, bolometer, philosopher, kilometer, astrologer, speedometer, subocular, thermometer, geographer, reconciler, odometer, siphonophore, hygrometer, chronometer, micrometer, hydrometer, compositor, copolymer, cosmographer, dock-walloper, ethnographer, femtometer, geometer, hectometer, horologer, involucre, lithographer, pedometer, pisanosaur, pyrometer, sclerometer, tintometer, typographer, viscometer

5 syllables:
interlocutor, lexicographer, salinometer, densitometer, myriameter, choreographer, piezometer, variometer, ovipositor, dynamometer, anemometer, katharometer, audiometer, mileometer, goniometer, galvanometer, sensitometer, inclinometer, actinometer, declinometer, tacheometer, magnetometer, bibliographer, craniometer, electrometer, eudiometer, oceanographer, radiographer, radiometer, refractometer

6 syllables:
interferometer, autobiographer, accelerometer, cinematographer, sphygmomanometer, evaporometer, telethermometer, historiographer, potentiometer, thermohydrometer

7 syllables:
radiomicrometer

8 syllables:
electrodynamometer