According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 48 words with the pattern A---O-. That is, six letter words with 1st letter A and 5th letter O. In alphabetical order, they are:

abator

abloom

abmhos

acajou

accloy

acknow

action

addios

addoom

adobos

aggros

agloos

agorot

ahchoo

alamos

alcool

alison

aliyos

aliyot

allyou

alsoon

amadou

amatol

amazon

amidol

amigos

amnion

amnios

analog

anchor

anchos

andros

anglos

anyhow

apedom

apolog

appros

arccos

archon

aspros

astoop

aswoon

athrob

audios

author

avisos

awetos

azygos