Here are some other adjectives related to "fool":
* Foolish - lacking good sense or judgment
* Silly - lacking seriousness or sense
* Stupid - lacking intelligence or common sense
* Naive - lacking experience, wisdom, or judgment
* Dull - lacking intelligence or sharpness of mind
* Simple - lacking in complexity or sophistication
* Absentminded - forgetful and preoccupied
* Scatterbrained - lacking in concentration and focus
* Clueless - unaware of what is happening or what is expected