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

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.