4 letter words:
fino7,
firn7,
foin7,
four7,
info7,
inro4,
iron4,
noir4,
nori4,
ourn4,
roin4,
ruin4,
3 letter words:
fin6,
fir6,
fon6,
for6,
fou6,
fro6,
fun6,
fur6,
orf6,
rif6,
ufo6,
ion3,
nor3,
nur3,
our3,
rin3,
run3,
uni3,
urn3,
2 letter words:
if5,
of5,
in2,
io2,
no2,
nu2,
oi2,
on2,
or2,
ou2,
un2,
ur2,