Noun and の adjective
こもん
彼は良いバスケ部の顧問だとの評判があります。
Rumor has it, he’s a good coach for the basketball club.
The people who will review a problem are those who know more about the problems. They are the advisors.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.