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% replaces any number of letters (la% - lake, lamp)_ replaces one letter (ca_ - car, cat)

Crossword clues for Extreme foolishness 6 letters:

LUNACY: Extreme foolishness
INSANE: Extremely foolish
IDIOCY: Extreme foolishness
LOONY: Extremely foolish
INSANITY: Extreme foolishness
ASININE: Extremely foolish