A somewhat literary or formal term for a foolish person; less common in casual speech than 馬鹿.
He called himself a fool.
The Fool (Tarot card)
Refers specifically to the Tarot card; used in fortune-telling contexts.
The Fool tarot card represents a new beginning.
愚者 means a foolish person, the direct opposite of the wise 賢人.
Standard kanji spelling.
Compound of 愚 (foolish) and 者 (person). The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning 'foolish person'.