9 letter words:
bountiful14,
7 letter words:
botulin9,
tubulin9,
unbuilt9,
6 letter words:
tubful11,
tinful9,
tufoli9,
unbolt8,
5 letter words:
flint8,
flout8,
fount8,
futon8,
unfit8,
biont7,
blunt7,
built7,
unlit5,
until5,
4 letter words:
flub9,
filo7,
fino7,
flit7,
foil7,
foin7,
font7,
foul7,
info7,
lift7,
loft7,
tofu7,
bint6,
blin6,
blot6,
boil6,
bolt6,
bout6,
bunt6,
obit6,
into4,
lino4,
lint4,
lion4,
litu4,
loin4,
loti4,
lout4,
lunt4,
noil4,
toil4,
tolu4,
unit4,
unto4,
3 letter words:
fib8,
fob8,
fub8,
fil6,
fin6,
fit6,
flu6,
fon6,
fou6,
fun6,
oft6,
bin5,
bio5,
bit5,
bot5,
bun5,
but5,
lib5,
lob5,
nib5,
nob5,
nub5,
obi5,
tub5,
ion3,
lin3,
lit3,
lot3,
nil3,
nit3,
not3,
nut3,
oil3,
out3,
til3,
tin3,
ton3,
tui3,
tun3,
ulu3,
2 letter words:
if5,
of5,
bi4,
bo4,
in2,
it2,
li2,
lo2,
no2,
nu2,
oi2,
on2,
ti2,
to2,
un2,
ut2,