8 letter words:
subfixes20,
6 letter words:
subfix18,
busies8,
5 letter words:
fixes15,
sixes12,
fuses8,
seifs8,
bises7,
buses7,
issue5,
4 letter words:
ibex13,
fibs9,
fubs9,
feis7,
fess7,
feus7,
fuse7,
fuss7,
seif7,
bise6,
buss6,
sibs6,
subs6,
seis4,
sies4,
sues4,
uses4,
3 letter words:
fix13,
sex10,
six10,
xis10,
fib8,
fub8,
efs6,
fes6,
feu6,
fie6,
ifs6,
sif6,
bes5,
bis5,
bus5,
sib5,
sub5,
ess3,
sei3,
sis3,
sue3,
sui3,
sus3,
use3,
2 letter words:
ex9,
xi9,
xu9,
ef5,
fe5,
if5,
be4,
bi4,
es2,
is2,
si2,
us2,
