6 letter words:
rubati8,
5 letter words:
briar7,
bruit7,
urbia7,
urari5,
4 letter words:
abri6,
abut6,
bait6,
birr6,
brat6,
brit6,
brut6,
bura6,
burr6,
tabu6,
tuba6,
airt4,
3 letter words:
arb5,
bar5,
bat5,
bit5,
bra5,
brr5,
bur5,
but5,
rib5,
rub5,
tab5,
tub5,
urb5,
air3,
ait3,
art3,
rai3,
rat3,
ria3,
rut3,
tar3,
tau3,
tui3,
uta3,
2 letter words:
ab4,
ba4,
bi4,
ai2,
ar2,
at2,
it2,
ta2,
ti2,
ut2,