### Clue: Extremely foolish to reject Irish girl's song (8)
### Answer: MADRIGAL 
 ### Explanation: Definition: song
 MAD(extremely foolish, as in "you're mad to attempt that stunt") **plus**(to) **reversal of**(reject) IR(abbrev. for "Irish") + GAL(slang for a girl).
Answer: A type of 16-17C song for unaccompanied voices.