7 letter words:
unburnt9,
6 letter words:
unturn6,
5 letter words:
brung8,
brunt7,
burnt7,
urubu7,
grunt6,
4 letter words:
bung7,
burg7,
grub7,
brut6,
bunn6,
bunt6,
burn6,
gurn5,
guru5,
rung5,
trug5,
tung5,
runt4,
turn4,
3 letter words:
bug6,
gub6,
bru5,
bun5,
bur5,
but5,
nub5,
rub5,
tub5,
urb5,
gnu4,
gun4,
gur4,
gut4,
rug4,
tug4,
nun3,
nur3,
nut3,
run3,
rut3,
tun3,
urn3,
utu3,
2 letter words:
gu3,
ug3,
nu2,
un2,
ur2,
ut2,