5 letter words:
inorb7,
orpin7,
prion7,
proin7,
robin7,
4 letter words:
prob8,
biro6,
born6,
brin6,
brio6,
pion6,
pirn6,
porn6,
inro4,
iron4,
noir4,
nori4,
roin4,
3 letter words:
bop7,
bin5,
bio5,
boi5,
bon5,
bor5,
bro5,
nib5,
nip5,
nob5,
obi5,
orb5,
pin5,
pir5,
poi5,
pro5,
rib5,
rip5,
rob5,
ion3,
nor3,
rin3,
2 letter words:
bi4,
bo4,
ob4,
op4,
pi4,
po4,
in2,
io2,
no2,
oi2,
on2,
or2,