Achates is a noun that refers to a faithful friend.
Our word of the day comes from an epic poem called Aeneid. In the story, Achates accompanies a Trojan leader named Aeneas everywhere in his adventures. Prior to being featured in the poem by Vergil, both characters originated in Greek mythology.
When trying out a new standup comedy routine, I like to rehearse it in front of an Achates or two. Only a faithful friend will have the courage to tell you when you’re not funny.