7 letter words:
catboat11,
6 letter words:
attach11,
5 letter words:
batch12,
botch12,
chott10,
cotta7,
4 letter words:
bach11,
baht9,
bath9,
both9,
chao9,
chat9,
tach9,
oath7,
that7,
acta6,
batt6,
boat6,
bota6,
bott6,
coat6,
taco6,
tact6,
3 letter words:
bah8,
hob8,
cab7,
cob7,
aah6,
aha6,
hao6,
hat6,
hot6,
tho6,
aba5,
abo5,
act5,
baa5,
bat5,
boa5,
bot5,
cat5,
cot5,
oba5,
oca5,
tab5,
att3,
oat3,
tao3,
tat3,
tot3,
2 letter words:
ah5,
ha5,
ho5,
oh5,
ab4,
ba4,
bo4,
aa2,
at2,
ta2,
to2,