1screw·ball 
/ˈskru:ˌbɑ:l/ noun
plural screw·balls /ˈskru:ˌbɑ:l/ noun [count] 1 baseball : a pitch that is thrown with spin so that the ball curves in a direction that is opposite to the direction of a curveball 2 chiefly US, informal : a crazy person : a person who is not able to think in a clear or sensible way
▪ She really did that? What a screwball.
▪ She really did that? What a screwball.
