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, myectomy, necrectomy, nephrectomy, neurectomy, nymphectomy, orchectomy, ostectomy, penectomy, phallectomy, phlebectomy, phrenectomy, pleurectomy, pneumectomy, proctectomy, pulpectomy, radectomy, rectectomy, sclerectomy, septectomy, splenectomy, 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, sympathetectomy, trabeculectomy, ureterectomy, vermilionectomy

7 syllables:
acetabulectomy, angioneurectomy, chemopallidectomy, costotransversectomy, cryothalamectomy, cystoprostatectomy, dacryocystectomy, diverticulectomy, epididymectomy, gastropylorectomy, hemicorporectomy, hemicraniectomy, hemilaminectomy, hemithyroidectomy, oophorocystectomy, parathyroidectomy, pericardiectomy, proctosigmoidectomy, 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:
pancreatoduodenectomy

11 syllables:
pancreaticoduodenectomy

12 syllables:
hysterosalpingo-oophorectomy

2 syllables:
thessaly

3 syllables:
pregnancy, flexibly, melody, legatee, steadily, severally, splendidly, pleasantly, legacy, entity, bestially, cecity, felony, necropsy, messily, preciously, jealousy, restfully, recipe, sesame, enemy, ecstasy, tendency, seventy, entropy, ebony, especially, debauchee, pedigree, credibly, specialty, presently, gemini, destiny, venally, zealotry, mentally, density, heavily, tensity, leprosy, dreadfully, helpfully, prelacy, peasantry, lengthily, heavenly, elegy, readily, testily, specially, clemency, medically, embassy, tenantry, endlessly, weaponry, velvety, helplessly, empathy, tenancy, equity, pleasantry, zestfully, centrally, jealously, chemically, penalty, threnody, sensibly, kennedy, devilry, deputy, remedy, breathlessly, brevity, secondly, revelry, chemistry, pedantry, enmity, 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:
inflexibly, dependency, supremacy, convexity, theosophy, incredibly, fidelity, unpleasantly, integrity, potentially, incessantly, rebelliously, transcendency, death penalty, allegedly, detestably, anemone, longevity, acceptably, tremendously, repentantly, ineffably, resplendently, essentially, flux density, extremity, ascendancy, nonentity, desperately, schenectady, indemnity, expectancy, perplexity, intrepidly, ostensibly, identity, incessancy, necessity, dependably, sententiously, resplendency, lamentably, complexity, solemnity, successfully, inequity, contemptuously, amenity, discrepancy, sequentially, federally, unsteadily, separately, telepathy, intensity, insensibly, telemetry, respectfully, ascendency, preferably, licentiously, low density, regrettably, respectably, hegemony, heredity, tentatively, generally, infectiously, perceptibly, penelope, serenity, 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:
disrespectfully, penitentially, high fidelity, irreverently, macrencephaly, unacceptably, deferentially, confederacy, geochemistry, photochemistry, mask of pregnancy, biochemistry, independency, accidentally, independently, conscientiously, tubal pregnancy, abstemiously, microcephaly, reverentially, fundamentally, incidentally, vapor density, eventually, white supremacy, anencephaly, professionally, reprehensibly, unsuccessfully, intemperately, life expectancy, open sesame, sentimentally, providentially, exceptionally, consequentially, 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:
radiochemistry, physical chemistry, unconventionally, experimentally, interdependency, coincidentally, cercopithecidae, biogeography, impetuosity, unintentionally, cosmetic dentistry, inconsequentially, manifest destiny, immunochemistry, environmentally, electrochemistry, relative density, organic chemistry, anas penelope, change of integrity, genus penelope, militant tendency, pedal extremity, unsentimentally

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

8 syllables:
conformational entropy, interpersonal chemistry