8 letter words:
frostbit13,
7 letter words:
bistort9,
6 letter words:
fortis9,
fritts9,
bistro8,
britts8,
orbits8,
5 letter words:
forbs10,
first8,
foist8,
forts8,
frits8,
fritt8,
frost8,
rifts8,
tofts8,
biros7,
bitts7,
borts7,
botts7,
brios7,
brits7,
britt7,
obits7,
orbit7,
riots5,
rotis5,
tiros5,
toits5,
torsi5,
torts5,
trios5,
trois5,
trots5,
4 letter words:
fibs9,
fobs9,
forb9,
firs7,
fist7,
fits7,
fort7,
frit7,
rifs7,
rift7,
sift7,
soft7,
toft7,
bios6,
biro6,
bits6,
bitt6,
bort6,
bots6,
bott6,
brio6,
bris6,
brit6,
bros6,
obis6,
obit6,
orbs6,
ribs6,
robs6,
sorb6,
stob6,
orts4,
riot4,
roti4,
rots4,
sori4,
sort4,
stir4,
stot4,
tiro4,
tits4,
toit4,
tori4,
tors4,
tort4,
tost4,
tots4,
trio4,
trot4,
3 letter words:
fib8,
fob8,
fir6,
fit6,
for6,
fro6,
ifs6,
oft6,
rif6,
bio5,
bis5,
bit5,
bos5,
bot5,
bro5,
obi5,
orb5,
rib5,
rob5,
sib5,
sob5,
its3,
ors3,
ort3,
rot3,
sir3,
sit3,
sot3,
sri3,
tis3,
tit3,
tor3,
tot3,
2 letter words:
if5,
of5,
bi4,
bo4,
is2,
it2,
oi2,
or2,
os2,
si2,
so2,
ti2,
to2,