9 letter words:
finickier18,
6 letter words:
firkin13,
knifer13,
ickier12,
nicker12,
inkier10,
irenic8,
5 letter words:
kefir12,
knife12,
icker11,
ficin10,
inker9,
reink9,
finer8,
infer8,
icier7,
nicer7,
ricin7,
4 letter words:
feck13,
fink11,
kerf11,
kief11,
neck10,
nick10,
reck10,
rick10,
fice9,
keir8,
kern8,
kier8,
kine8,
kirn8,
rink8,
fern7,
fine7,
fire7,
firn7,
neif7,
reif7,
rife7,
cine6,
cire6,
nice6,
rice6,
rein4,
3 letter words:
kef10,
kif10,
ick9,
ink7,
irk7,
ken7,
kin7,
kir7,
fen6,
fer6,
fie6,
fin6,
fir6,
ref6,
rif6,
ice5,
rec5,
ern3,
ire3,
rei3,
rin3,
2 letter words:
ki6,
ef5,
fe5,
if5,
en2,
er2,
in2,
ne2,
re2,