5 letter words:
fermi10,
finer8,
infer8,
miner7,
4 letter words:
firm9,
fern7,
fine7,
fire7,
firn7,
neif7,
reif7,
rife7,
emir6,
mien6,
mine6,
mire6,
rime6,
rein4,
3 letter words:
fem8,
fen6,
fer6,
fie6,
fin6,
fir6,
ref6,
rif6,
men5,
mir5,
nim5,
rem5,
rim5,
ern3,
ire3,
rei3,
rin3,
2 letter words:
ef5,
fe5,
if5,
em4,
me4,
mi4,
en2,
er2,
in2,
ne2,
re2,