6 letter words:
borzoi17,
5 letter words:
brook11,
iroko9,
4 letter words:
bozo15,
orzo13,
zori13,
birk10,
book10,
bork10,
kobo10,
rook8,
biro6,
birr6,
boor6,
brio6,
broo6,
3 letter words:
biz14,
zoo12,
kob9,
irk7,
kir7,
koi7,
kor7,
bio5,
boo5,
bro5,
brr5,
obi5,
orb5,
rib5,
rob5,
2 letter words:
ki6,
bi4,
bo4,
oi2,
or2,