2 syllables:
wednesday

3 syllables:
ash wednesday, audibly, balmily, blossomy, bodily, bonduc tree, bonhomie, botany, bottletree, broccoli, caudally, colloquy, colony, comedy, commonly, comparably, conakry, connally, consciously, constancy, constantly, cosily, cozily, crotchety, dottily, foxily, gossipy, guenon monkey, homily, honestly, honesty, hostelry, hostilely, knobbly, modestly, modesty, monody, monstrously, novelty, noxiously, obloquy, oddity, odyssey, ology, policy, polity, possibly, probably, prodigy, progeny, promisee, prophecy, prophesy, prosody, psalmody, ptolemy, quality, quantity, rocketry, romany, rommany, rottenly, sodomy, solidly, sovereignty, squalidly, stodgily, talkily, wallaby, wannabe, wannabee, wantonly, watchfully, wobbly

4 syllables:
aerology, agrology, agronomy, algometry, allometry, allotropy, androgeny, anomaly, anthology, apogamy, apology, apostrophe, arthrography, arthroscopy, astrolatry, astrology, astrometry, astronomy, atrocity, autocracy, autogeny, autonomy, bardolatry, biogeny, biography, biology, bureaucracy, cacography, cacophony, calabash tree, callosity, cartography, child prodigy, chronology, commodity, conchology, cosmography, cosmolatry, cytology, democracy, demography, demonstrably, despondency, despondently, dichotomy, dishonesty, doxology, ecology, economy, enology, equality, ethnography, ethnology, ethology, exogamy, farce comedy, ferocity, fluoroscopy, frivolity, gastronomy, geodesy, geography, geology, geometry, globosity, glyptography, gymnosophy, high quality, histology, homogeny, homology, horology, hydrography, hydrology, hydrometry, hypocrisy, idolatry, immodestly, immodesty, impossibly, improbably, inconstancy, insolvency, isogamy, isometry, limnology, lithography, lithotomy, lordolatry, low comedy, low quality, mahogany, mammalogy, mammography, monocracy, monogamy, monopoly, monopsony, monotony, monstrosity, morphology, mycology, mythology, naprapathy, neology, neurology, nosology, obnoxiously, old colony, oncology, ontogeny, ontology, optometry, orthography, otology, pathology, penology, petrology, philology, philosophy, phonology, photography, phrenology, phylogeny, phytology, planography, plutocracy, pomology, pornography, porosity, precocity, prime quantity, proctology, psephology, psychology, psychometry, pyrolatry, responsibly, seismology, self-consciously, serology, shape constancy, sinology, size constancy, sonography, spectrometry, spectroscopy, symbolatry, tautology, tax policy, technology, tetralogy, theocracy, theology, theosophy, thermometry, tocology, top-quality, topography, topolatry, trade policy, tuatha de, typography, unconsciously, urology, velocity, venography, verbolatry, verbosity, virology, viscometry, viscosity, with modesty, zoolatry, zoology

5 syllables:
aetiology, anemography, anemometry, angiology, animosity, anorthography, anthropolatry, anthropology, anthropometry, arborolatry, archaeology, archeology, aristocracy, audiology, audiometry, axiology, bibliography, bibliolatry, brightness constancy, cardiography, cardiology, celioscopy, child psychology, choreography, chromatography, climatology, color constancy, complex quantity, constant quantity, criminology, crystallography, curiosity, defence policy, defense policy, demonolatry, densitometry, depth psychology, dermatology, diabolatry, disconsolately, egyptology, embryology, entomology, eschatology, etiology, etymology, fiscal policy, floating policy, foreign policy, genealogy, generosity, gerontology, glutinosity, grandiosity, greek mythology, gynaecology, gynaeolatry, gynecology, gyneolatry, haematology, hagiography, hagiolatry, hagiology, heliolatry, hematology, high technology, iconolatry, ideography, ideology, idiolatry, immunology, inequality, irresponsibly, laparoscopy, laparotomy, lexicography, lexicology, mass spectroscopy, mediocrity, methodology, mineralogy, news photography, norse mythology, numerosity, oceanography, oenology, ophthalmology, ornithology, palaeology, paleography, paleology, passamaquody, pharmacology, physiography, physiology, plane geometry, poenology, preciosity, primatology, radiography, radiology, radioscopy, rail technology, rheumatology, roentgenography, scientology, social policy, sociology, sociometry, spelaeology, speleology, sumerology, symbololatry, terminology, thaumatolatry, toxicology, tragicomedy, trigonometry, true anomaly, true mahogany, tuberosity, unknown quantity, unselfconsciously, uranology, without modesty, xerography

6 syllables:
agrobiology, antimonopoly, applied psychology, arteriography, assyriology, autobiography, bacteriology, biogeography, biotechnology, cedar mahogany, cholangiography, cholelithotomy, christian theology, chromolithography, cinematography, compound morphology, cuban mahogany, decline in quality, definite quantity, endocrinology, epistemology, escape velocity, folk etymology, geomorphology, glottochronology, human ecology, hypervelocity, insurance policy, legal philosophy, mammothermography, managed economy, market economy, maternal quality, meteorology, microbiology, mining geology, moral philosophy, musical comedy, muzzle velocity, neurobiology, neuropsychology, numismatology, offset lithography, palaeobotany, palaeontology, palaetiology, paleobotany, paleontology, paletiology, parapsychology, parental quality, paternal quality, photolithography, powder photography, protozoology, psychopathology, relative quantity, religiosity, roman mythology, seriocomedy, social democracy, social psychology, solid geometry, telephotography, token economy, ultrasonography, voluminosity

7 syllables:
absolute viscosity, african mahogany, anesthesiology, animal psychology, bioclimatology, classical mythology, clinical neurology, clinical psychology, cognitive psychology, column chromatography, communist economy, computer technology, descriptive geometry, dialect geography, doctor of optometry, doctor of philosophy, doctor of theology, dynamic viscosity, economic policy, electromyography, epidemiology, genetic psychology, honduras mahogany, immunopathology, indefinite quantity, linguistic geography, marine archaeology, marine archeology, master of theology, natural philosophy, natural theology, neurophysiology, numerical quantity, palaeobiology, palaeodendrology, palaeoethnography, palaeogeography, palaeogeology, palaeopathology, palaeornithology, palaeozoology, paleobiology, paleodendrology, paleoethnography, paleogeography, paleogeology, paleomammalogy, paleopathology, paleornithology, paleozoology, paper chromatography, parametric quantity, philippine mahogany, physical geography, projective geometry, protoanthropology, protoarchaeology, protoarcheology, psychopharmacology, psychophysiology, radio astronomy, situation comedy, socialist economy, social anthropology, sociobiology, spherical geometry, terminal velocity, unit of viscosity, variable quantity

8 syllables:
analytic geometry, automotive technology, bachelor of theology, capitalist economy, comparative psychology, congenital anomaly, coordinate geometry, cultural anthropology, department of biology, department of philosophy, department of psychology, descriptive anthropology, differential psychology, dominican mahogany, economic geography, economic geology, elementary geometry, empiricist philosophy, human paleontology, hyperbolic geometry, industrial psychology, large indefinite quantity, micropaleontology, molecular biology, national trading policy, palaeoclimatology, paleoanthropology, paleoclimatology, parabolic geometry, petroleum geology, physical anthropology, political economy, proprietary colony, small indefinite quantity, transcendental philosophy

9 syllables:
african scented mahogany, analytical geometry, coefficient of viscosity, communications technology, department of anthropology, department of sociology, developmental psychology, experimental psychology, parliamentary democracy, underwater archaeology, underwater archeology

10 syllables:
physiological psychology

11 syllables:
council on environmental policy

12 syllables:
digital communications technology