3 syllables:
-ectomy, ectomy

4 syllables:
antrectomy, arthrectomy, bullectomy, bursectomy, canthectomy, carpectomy, cecectomy, cheilectomy, cirsectomy, colectomy, colpectomy, cordectomy, corectomy, corpectomy, costectomy, cystectomy, discectomy, diskectomy, frenectomy, fundectomy, gastrectomy, glomectomy, glossectomy, gyrectomy, isthmectomy, lensectomy, lipectomy, lobectomy, lumpectomy, mammectomy, mastectomy, myectomy, necrectomy, nephrectomy, neurectomy, nymphectomy, orchectomy, ostectomy, penectomy, phallectomy, phlebectomy, phrenectomy, pleurectomy, pneumectomy, proctectomy, pulpectomy, radectomy, rectectomy, sclerectomy, septectomy, strumectomy, syndesmectomy, tarsectomy, tenectomy, testectomy, thrombectomy, thymectomy, topectomy, tubectomy, tylectomy, typhlectomy, vasectomy, vaxectomy, vitrectomy, vulvectomy

5 syllables:
adenectomy, adipectomy, adnexectomy, apicectomy, appendectomy, atherectomy, blepharectomy, bunionectomy, callosectomy, capsulectomy, cardiectomy, cervicectomy, clitorectomy, coccygectomy, craniectomy, embolectomy, embryectomy, enterectomy, ethmoidectomy, facetectomy, fasciectomy, fistulectomy, fundusectomy, gangliectomy, gingivectomy, gonadectomy, hepatectomy, hymenectomy, hysterectomies, hysterectomy, iridectomy, jejunectomy, keratectomy, laminectomy, laparectomy, laryngectomee, laryngectomy, lymphangiectomy, mastoidectomy, meniscectomy, mucosectomy, myomectomy, myringectomy, necrosectomy, odontectomy, omentectomy, omphalectomy, onychectomy, oophorectomy, ophthalmectomy, orchidectomy, orchiectomy, patellectomy, peritectomy, pharyngectomy, pneumonectomy, polypectomy, prostatectomy, pylorectomy, quadrantectomy, rhytidectomy, salpingectomy, segmentectomy, sequestrectomy, sigmoidectomy, stapedectomy, sympathectomy, synovectomy, tenonectomy, thyroidectomy, tonsillectomy, trachelectomy, turbinectomy, tympanectomy, urethrectomy, uvulectomy, vaginectomy, vertebrectomy

6 syllables:
adenoidectomy, adrenalectomy, alveolectomy, aneurysmectomy, apicoectomy, appendicectomy, arteriectomy, astragalectomy, cholecystectomy, clitoridectomy, duodenectomy, endarterectomy, esophagectomy, haemorrhoidectomy, hemicolectomy, hemiglossectomy, hemipelvectomy, hemispherectomy, hemorrhoidectomy, hydrocelectomy, hypophysectomy, labyrinthectomy, lymphadenectomy, nephroureterectomy, oesophagectomy, ovariectomy, pancreatectomy, panhysterectomy, panniculectomy, parotidectomy, pericardectomy, pinealectomy, proctocolectomy, radiculectomy, simple mastectomy, sympathetectomy, trabeculectomy, ureterectomy, vermilionectomy

7 syllables:
acetabulectomy, angioneurectomy, chemopallidectomy, costotransversectomy, cryothalamectomy, cystoprostatectomy, dacryocystectomy, diverticulectomy, epididymectomy, gastropylorectomy, hemicorporectomy, hemicraniectomy, hemilaminectomy, hemithyroidectomy, oophorocystectomy, parathyroidectomy, pericardiectomy, proctosigmoidectomy, radical mastectomy, suprarenalectomy, thromboembolectomy, thromboendarterectomy, total hysterectomy, varicocelectomy

8 syllables:
adenotonsillectomy, hysteromyomectomy, hysterosalpingectomy, laparohysterectomy, oophorosalpingectomy, radical hysterectomy, ureteronephrectomy

9 syllables:
abdominohysterectomy, hystero-oophorectomy, ovariohysterectomy, salpingo-oophorectomy

10 syllables:
modified radical mastectomy, pancreatoduodenectomy

11 syllables:
pancreaticoduodenectomy

12 syllables:
hysterosalpingo-oophorectomy

2 syllables:
thessaly

3 syllables:
severally, splendidly, pleasantly, messily, tendency, ebony, pedigree, credibly, gemini, venally, leprosy, prelacy, lengthily, elegy, readily, tenantry, weaponry, helplessly, equity, zestfully, remedy, breathlessly, brevity, revelry, flexibly, melody, steadily, entity, jealousy, restfully, enemy, seventy, entropy, tensity, peasantry, clemency, velvety, threnody, sensibly, devilry, chemistry, pedantry, pregnancy, legacy, bestially, cecity, necropsy, sesame, zealotry, mentally, density, dreadfully, helpfully, testily, specially, embassy, tenancy, pleasantry, centrally, kennedy, deputy, secondly, enmity, legatee, felony, preciously, recipe, ecstasy, especially, debauchee, specialty, presently, destiny, heavily, heavenly, medically, endlessly, empathy, jealously, chemically, penalty, benghazi, dextrously, ectropy, emigree, evilly, fecklessly, jejunely, legibly, lemony, lenity, melanie, pebbly, pederasty, penally, resiny, self-pity, selflessly, senselessly, sentiency, stephanie, tepidly, trenchancy, trepidly, vengefully, yemeni, zestily

4 syllables:
theosophy, incessantly, rebelliously, transcendency, detestably, acceptably, resplendently, extremity, ascendancy, nonentity, expectancy, identity, necessity, dependably, lamentably, successfully, inequity, discrepancy, sequentially, unsteadily, ascendency, preferably, serenity, fidelity, unpleasantly, potentially, death penalty, tremendously, essentially, flux density, desperately, schenectady, intrepidly, ostensibly, sententiously, complexity, insensibly, telemetry, respectfully, respectably, hegemony, generally, inflexibly, dependency, supremacy, anemone, longevity, repentantly, ineffably, perplexity, resplendency, solemnity, contemptuously, amenity, federally, intensity, heredity, perceptibly, convexity, incredibly, integrity, allegedly, indemnity, incessancy, separately, telepathy, licentiously, low density, regrettably, tentatively, infectiously, penelope, acephaly, confessedly, defencelessly, domenici, forelady, illegibly, immensity, impendency, impetuously, inclemency, jack kennedy, lieutenancy, perplexedly, polemically, pretentiously, professedly, quiescency, refreshfully, relentlessly, revengefully, shell entity, unhelpfully, with empathy

5 syllables:
geochemistry, mask of pregnancy, eventually, life expectancy, sentimentally, exceptionally, consequentially, confederacy, biochemistry, accidentally, independently, tubal pregnancy, reverentially, white supremacy, professionally, disrespectfully, penitentially, irreverently, macrencephaly, abstemiously, incidentally, intemperately, open sesame, providentially, high fidelity, unacceptably, deferentially, photochemistry, independency, conscientiously, microcephaly, fundamentally, vapor density, anencephaly, reprehensibly, unsuccessfully, acrocephaly, change integrity, change intensity, clinocephaly, coalescency, create mentally, detrimentally, drunken revelry, field intensity, half-intensity, high-fidelity, hydrocephaly, intumescency, line of destiny, macrocephaly, megacephaly, mortal enemy, mountain ebony, nanocephaly, naval weaponry, of necessity, scaphocephaly, school of dentistry, unforgettably, unpretentiously, unrepentantly

6 syllables:
unconventionally, coincidentally, biogeography, unintentionally, environmentally, radiochemistry, physical chemistry, impetuosity, manifest destiny, interdependency, electrochemistry, organic chemistry, cercopithecidae, experimentally, cosmetic dentistry, inconsequentially, immunochemistry, relative density, anas penelope, change of integrity, genus penelope, militant tendency, pedal extremity, unsentimentally

7 syllables:
ovarian pregnancy, inorganic chemistry, magnetic flux density, paleogeography, abdominal pregnancy, department of chemistry, executive clemency, feeling of identity, john fitzgerald kennedy, magnetic intensity

8 syllables:
conformational entropy, interpersonal chemistry