Q: What are long homophones (words spelled differently but pronounced alike)?

A
uncomplementarinesses, uncomplimentarinesses (21)

The following homophones have different semantic roots and cannot be shortened by dropping prefixes or suffixes. Each contains the most letters for its number of words.

seven-way
scissel, scissile, Sicel, sisal, sisel, sissle, syssal (42)
six-way
cerous, cirrous/cirrhous, cirrus/cirrhus, scirrhus/scirrhous, seeress, serous (41)
five-way
senate, senet/sennet, senit/senat, sennet/sinnet, sennit/sennet/sinnet (28) carol, carrel, Karel, kerril, keryl (27)
four-way
baetyl, beadle, beetle, betel (23) chorea, correa, keriah, Korea (23)
three-way
cetaceous, psittaceous, setaceous (29) -- CETACEAN, PSITTACINE but no SETACEAN lickerish, licorice, liquorish (26) marischal, Marshall, martial (24) -- MARSHAL from the same root as MARISCHAL
two-way
recognizance, reconnaissance (12/14) -- COGNIZANCE but no CONNAISSANCE corespondent, correspondent (12/13) -- CORRESPOND but no CORESPOND calumniation, columniation (12) -- CALUMNY but no COLUMNY heteronomous, heteronymous (12) -- HETERONOMY but no HETERONYMY precedential, presidential (12) -- PRECEDENT and PRESIDENT are not homophones compellation, compilation (11/12) -- COMPILE but no (related) COMPELL acclamation, acclimation (11) -- ACCLIMATE but no ACCLAMATE androgenous, androgynous (11) -- ANDROGYN but no (related) ANDROGEN appalachian, appellation (11) depravation, deprivation (11) -- DEPRAVE and DEPRIVE are not homophones discography, diskography (11) -- DISKOGRAM but no DISCOGRAM quintillian, quintillion (11) repertorial, reportorial (11) -- REPERTORY versus REPORTER allegation, alligation (10) -- ALLEGE but no ALLIGE aplanatism, aplanetism (10) -- APLANAT but not APLANET asperation, aspiration (10) -- ASPERATE but no ASPIRATE caledonian, calydonian (10) caliginous, kaligenous (10) cariniform, coryneform (10) carinthian, corinthian (10) intendance, intendence (10) pediatrist, podiatrist (10) -- PEDIATRICS versus PODIATRY pertinence, purtenance (10) polypteris, polypterus (10) spencerian, spenserian (10) stationary, stationery (10) -- STATIONER but no STATIONAR uranometry, urinometry (10) -- URINOUS but no (related) URANOUS councillor, counselor (9/10) diaeretic, diarrhetic (9/10) ephemerous, ephemeris (9/10) lightning, lightening (9/10) allegator, alligator (9) -- ALLEGE but no ALLIGE censorial, sensorial (9) champaign, champagne (9) cilicious, silicious (9) corollate, correlate (9) hermetism, hermitism (9) millenary, millinary (9) manometer, monometer (9) precisian, precision (9) veracious, voracious (9)
phrases
Grothendieck K-theory, growth-and-decay theory

**** Unless noted otherwise, all words occur in Webster's Third New International Dictionary, Merriam-Webster, Springfield, MA, 1961.

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