Pronunciation: (skrOO'bôl"), [key]
1. Slang.an eccentric or whimsically eccentric person; a nut.
2. Baseball.a pitched ball that curves toward the side of the plate from which it was thrown.
Slang.eccentric or whimsically eccentric: What a screwball idea!
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.