9 letter words:
butterbur13,
6 letter words:
rubber10,
rubbet10,
tubber10,
bruter8,
butter8,
rutter6,
turret6,
5 letter words:
brute7,
buret7,
butte7,
butut7,
rebut7,
tuber7,
truer5,
utter5,
4 letter words:
bubu8,
burb8,
brer6,
brut6,
burr6,
bute6,
butt6,
rube6,
tube6,
ruer4,
ruru4,
tret4,
true4,
tutu4,
3 letter words:
bub7,
ebb7,
bet5,
brr5,
bru5,
bur5,
but5,
reb5,
rub5,
tub5,
urb5,
err3,
ret3,
rue3,
rut3,
tet3,
tut3,
ure3,
ute3,
utu3,
2 letter words:
be4,
er2,
et2,
re2,
te2,
ur2,
ut2,
