3 syllables:
almoner

3 syllables:
off-color, officer, softener, baltimore, saltcellar, congener, alcazar, blockbuster, bolivar, cocklebur, colander, columnar, commissar, commodore, commoner, common murre, conifer, cottager, globular, gobbler, godmother, gospeler, gospeller, gossamer, gossiper, groveller, hollander, holloware, hosteller, jocular, modeler, monitor, monomer, nodular, ocular, oliver, onager, polymer, pompadour, popular, promiser, promisor, quadrature, slopseller, sodbuster, swashbuckler, troposphere, wobbler

4 syllables:
flag officer, staff officer, peace officer, line officer, field officer, kilometre, algometer, assam rubber, astrologer, astronomer, atmometer, bilocular, binocular, biographer, black hollander, chronometer, compositor, copolymer, cosmographer, demographer, dock-walloper, ethnographer, femtometer, geographer, geometer, heart monitor, hectometer, hodometer, horologer, hydrometer, hygrometer, involucre, kilometer, lithographer, micrometer, odometer, pedometer, philosopher, photographer, picometer, pisanosaur, pornographer, psychrometer, pyrometer, sclerometer, spectrometer, speedometer, spherometer, subocular, tachometer, thermometer, tintometer, typographer, unpopular, viscometer

5 syllables:
water softener, petty officer, police officer, warrant officer, air thermometer, anemometer, audiometer, bibliographer, choreographer, craniometer, declinometer, densitometer, dynamometer, electrometer, eudiometer, gas thermometer, goniometer, inclinometer, interlocutor, lexicographer, magnetometer, mass spectrometer, meat thermometer, mileometer, oceanographer, piezometer, press photographer, radiographer, radiometer, refractometer, salinometer, sensitometer, simon bolivar, tacheometer, variometer, vinyl polymer

6 syllables:
commissioned officer, general officer, commanding officer, chief petty officer, probation officer, accelerometer, african monitor, autobiographer, beckman thermometer, candy thermometer, cardiac monitor, cinematographer, cubic kilometer, evaporometer, historiographer, interferometer, oven thermometer, platinum thermometer, potentiometer, silicone polymer, telethermometer, thermohydrometer

7 syllables:
executive officer, centigrade thermometer, clinical thermometer, electric thermometer, fahrenheit thermometer, mercury thermometer, political commissar, radiomicrometer, resistance thermometer, reversing thermometer, vernier micrometer

8 syllables:
chief operating officer, chief executive officer, electrodynamometer

9 syllables:
electronic fetal monitor, radio interferometer

11 syllables:
maximum and minimum thermometer