3 syllables:
quiddity

4 syllables:
acidity, acridity, algidity, aridity, avidity, calidity, callidity, cupidity, fervidity, fixidity, flaccidity, floridity, fluidity, fulgidity, fumidity, gelidity, gravidity, hispidity, humidity, lanquidity, limpidity, liquidity, lividity, lucidity, marcidity, morbidity, pallidity, pavidity, pinguidity, placidity, prigidity, putidity, rabidity, rancidity, rapidity, rigidity, sapidity, solidity, squalidity, stolidity, stupidity, tepidity, timidity, torpidity, trepidity, tumidity, turbidity, validity, vapidity, vastidity, viridity, viscidity, vividity

5 syllables:
anacidity, comorbidity, illiquidity, insolidity, invalidity, pellucidity, with validity

6 syllables:
hyperacidity, hypoacidity, pseudorapidity, semiaridity, semifluidity, semiliquidity, superacidity, superfluidity

7 syllables:
relative humidity, semipellucidity

3 syllables:
civilly, cliquishly, critically, cryptically, cynically, dimity, fidgety, fishily, fittingly, gibingly, gimmickry, hillbilly, imagery, impishly, killingly, limpidly, lingeringly, mimicry, ministry, physically, pidlimdi, politically, principally, realty, rigidly, sickeningly, swimmingly, trinity, trippingly, typically, whimsically, wickedly, willingly, wittingly

4 syllables:
activity, admittedly, affinity, assiduity, auspiciously, befittingly, bewitchingly, capriciously, complicity, convincingly, derisively, duplicity, ethnicity, exquisitely, facility, fertility, forgivingly, gentility, gracility, humility, infinity, iniquity, intrinsically, judiciously, linguistically, long-windedly, mobility, motility, obliquity, pacifically, passivity, perniciously, publicity, sidesplittingly, simplicity, specifically, stability, statistically, sterility, sublimity, submissively, terrifically, tonicity, tranquility, tranquillity, ubiquity, uncivilly, uncritically, unthinkingly, unwillingly, unwittingly, vicinity, vindictively, virginity

5 syllables:
affability, altruistically, anonymity, arability, atonicity, audibility, authenticity, avariciously, bendability, breakability, changeability, credibility, culpability, curability, directivity, disability, durability, edibility, effectivity, egotistically, equanimity, fallibility, friability, gullibility, health facility, immobility, immotility, impassivity, inability, inactivity, inauspiciously, incivility, infertility, injudiciously, instability, liability, longanimity, magnanimity, meretriciously, movability, multiplicity, objectivity, obsessivity, optimistically, palpability, pessimistically, plausibility, pliability, portability, productivity, provability, ratability, readability, realistically, receptivity, reflexivity, scientifically, sensibility, sensitivity, serendipity, sociability, solubility, spinnability, squeezability, stainability, subjectivity, suitability, synchronicity, synonymity, taxability, tenability, tractability, unanimity, unconvincingly, unforgivingly, visibility, volubility

6 syllables:
accessibility, achievability, admirability, adorability, advisability, agreeability, alterability, amenability, answerability, assailability, attainability, availability, believability, characteristically, comparability, conceivability, convertibility, corruptibility, delectability, demonstrability, dependability, desirability, destructibility, discernability, dispensability, dissolubility, docking facility, eligibility, exchangeability, formidability, hyperactivity, immovability, impalpability, impossibility, impregnability, inaudibility, incredibility, inculpability, incurability, indictability, infallibility, inflexibility, insolubility, interactivity, intractability, invincibility, irascibility, manageability, maneuverability, marriageability, measurability, navigability, noticeability, overactivity, penal facility, penetrability, perdurability, perfectability, perfectibility, permeability, permissibility, predictability, profitability, rateability, replaceability, respectability, separability, serviceability, sustainability, tax liability, transferability, transmutability, transposability, unchangeability, unrealistically, unsociability, variability, vulnerability

7 syllables:
associability, athletic facility, companionability, impenetrability, imperfectibility, impermeability, impermissibility, inadvisability, incompatibility, inconceivability, incorruptibility, indestructibility, indispensability, indomitability, indubitability, inevitability, inexorability, interchangeability, invariability, invulnerability, manipulability, quantifiability, reproducibility, unalterability, unavailability, uncharacteristically, undependability, understandability, undesirability, unexchangeability, unmalleability, unpredictability, unprofitability, unquestionability, unreliability, unrespectability

8 syllables:
incomprehensibility, incontrovertibility, indefatigability, irreproducibility, limited liability

9 syllables:
recreational facility