fol·ly 
(fŏlē)
(fŏlē)n. pl. fol·lies
1. Lack of good sense, understanding, or foresight: an act of folly
2.
a. An act or instance of foolishness: regretted the follies of his youth.
b. A costly undertaking having an absurd or ruinous outcome.
3. follies (used with a sing. or pl. verb) An elaborate theatrical revue consisting of music, dance, and skits.
4. A structure, such as a pavilion in a garden, that is chiefly decorative rather than practical in purpose.
[Middle English folie, from Old French, from fol, foolish, from Late Latin follis, windbag, fool; see FOOL.]
- house of correction
- House of Delegates
- house officer
- House of Lords
- house of mirrors
- House of Representatives
- house organ
- housepainter
- house painter
- houseparent
- house party
- houseperson
- house physician
- houseplant
- house-proud
- house-raising
- houseroom
- house seat
- housesit
- housesitter
- house snake
- house sparrow
- house staff
- housetop
- house trailer