9 letter words:
perturber13,
7 letter words:
perturb11,
6 letter words:
burpee10,
berret8,
beurre8,
bruter8,
burrer8,
perter8,
repure8,
repute8,
ureter6,
5 letter words:
beret7,
breer7,
brere7,
brute7,
buret7,
erupt7,
peter7,
petre7,
puree7,
purer7,
rebut7,
rupee7,
tuber7,
upter7,
truer5,
4 letter words:
beep8,
burp8,
pube8,
beer6,
beet6,
bere6,
bete6,
bree6,
brer6,
brrr6,
brut6,
burr6,
bute6,
peer6,
pere6,
pert6,
pree6,
puer6,
pure6,
purr6,
rube6,
rurp6,
tube6,
rete4,
ruer4,
teer4,
tree4,
true4,
3 letter words:
pub7,
bee5,
bet5,
brr5,
bru5,
bur5,
but5,
pee5,
per5,
pet5,
pre5,
pur5,
put5,
reb5,
rep5,
rub5,
tub5,
tup5,
urb5,
urp5,
ere3,
err3,
ree3,
ret3,
rue3,
rut3,
tee3,
ure3,
ute3,
2 letter words:
be4,
pe4,
up4,
ee2,
er2,
et2,
re2,
te2,
ur2,
ut2,