6 letter words:
unroof9,
unroot6,
5 letter words:
fount8,
front8,
futon8,
4 letter words:
font7,
foot7,
fort7,
four7,
roof7,
tofu7,
turf7,
onto4,
root4,
roto4,
rout4,
runt4,
toon4,
torn4,
toro4,
tour4,
turn4,
unto4,
3 letter words:
fon6,
for6,
fou6,
fro6,
fun6,
fur6,
oft6,
noo3,
nor3,
not3,
nut3,
ono3,
oot3,
ort3,
our3,
out3,
rot3,
run3,
rut3,
ton3,
too3,
tor3,
tun3,
urn3,
2 letter words:
of5,
no2,
nu2,
on2,
or2,
to2,
un2,
ut2,