5 letter words:
fubar10,
4 letter words:
barf9,
fart7,
frat7,
raft7,
tufa7,
turf7,
abut6,
brat6,
brut6,
bura6,
tabu6,
tuba6,
3 letter words:
fab8,
fub8,
aft6,
arf6,
far6,
fat6,
fur6,
arb5,
bar5,
bat5,
bra5,
bur5,
but5,
rub5,
tab5,
tub5,
urb5,
art3,
rat3,
rut3,
tar3,
tau3,
uta3,
2 letter words:
fa5,
ab4,
ba4,
ar2,
at2,
ta2,
ut2,