9 letter words:
interfirm14,
8 letter words:
ferritin11,
7 letter words:
rimfire12,
niftier10,
interim9,
mintier9,
termini9,
6 letter words:
firmer11,
infirm11,
finite9,
intime8,
minter8,
mirier8,
mitier8,
remint8,
retrim8,
rimier8,
trimer8,
tinier6,
5 letter words:
fermi10,
feint8,
finer8,
firer8,
frier8,
infer8,
refit8,
rifer8,
imine7,
merit7,
miner7,
mirin7,
miter7,
mitre7,
remit7,
rimer7,
timer7,
inert5,
inter5,
niter5,
nitre5,
trier5,
trine5,
4 letter words:
firm9,
fern7,
fine7,
fire7,
firn7,
fret7,
frit7,
neif7,
reft7,
reif7,
rife7,
rift7,
tref7,
emir6,
emit6,
item6,
mien6,
mine6,
mini6,
mint6,
mire6,
miri6,
mite6,
rime6,
term6,
time6,
trim6,
inti4,
nite4,
rein4,
rent4,
rite4,
tern4,
tier4,
tine4,
tire4,
3 letter words:
fem8,
eft6,
fen6,
fer6,
fet6,
fie6,
fin6,
fir6,
fit6,
ref6,
rif6,
men5,
met5,
mir5,
nim5,
rem5,
rim5,
ern3,
err3,
ire3,
net3,
nit3,
rei3,
ret3,
rin3,
ten3,
tie3,
tin3,
2 letter words:
ef5,
fe5,
if5,
em4,
me4,
mi4,
en2,
er2,
et2,
in2,
it2,
ne2,
re2,
ti2,