8 letter words:
furfuran14,
6 letter words:
furfur12,
5 letter words:
furan8,
4 letter words:
naff10,
nuff10,
raff10,
ruff10,
faun7,
faur7,
frau7,
furr7,
nurr4,
raun4,
ruru4,
unau4,
3 letter words:
aff9,
arf6,
auf6,
fan6,
far6,
fra6,
fun6,
fur6,
nur3,
ran3,
run3,
urn3,
2 letter words:
fa5,
an2,
ar2,
na2,
nu2,
un2,
ur2,
