[1] : The Collaborative International Dictionary of English v.0.48

screwball \screw"ball\, n.
   1. an eccentric or crazy person; an oddball.
      pjc

   2. baseball a baseball pitch that curves in the direction
      opposite to that of a curve ball.
      pjc

[2] : The Collaborative International Dictionary of English v.0.48

screwball \screw"ball\, adj.
   1. eccentric; zany; crazy; as, screwball antics; a screwball
      comedy.
      pjc

   2. ridiculously unsound; improbable or doomed to failure; --
      of plans or ideas; as, a screwball plan to raise cocoanuts
      in alaska.
      pjc

[3] : WordNet (r) 2.0

screwball
     adj : foolish; totally unsound; "an impractical solution"; "a
           crazy scheme"; "half-baked ideas"; "a screwball
           proposal without a prayer of working" syn: crazy, half-baked,
            softheaded
     n 1: a whimsically eccentric person syn: crackpot, crank, nut,
           nut case, nutcase, fruitcake
     2: a pitch with reverse spin that curves toward the side of the
        plate from which it was thrown
see also:
crazy half-baked softheaded crackpot crank nut 
nut case nutcase fruitcake 

[4] : Moby Thesaurus II by Grady Ward, 1.0

157 moby thesaurus words for "screwball":
   abnormal, alien, aliene, anomalous, balmy, bananas, barmy, bats,
   batty, beany, bedlamite, bonkers, borderline case, bowl, buggy,
   bughouse, bugs, case, cast, change of pace, change-up, character,
   chuck, chunk, crackbrain, crackers, crackpot, crank, crankish,
   cranky, crotchety, cuckoo, curve, daffy, dement, demoniac, deviant,
   deviative, different, ding-a-ling, dippy, divergent, dotty,
   downcurve, eccentric, energumen, erratic, exceptional, fanatic,
   fastball, fey, flake, flaky, fling, flip, flipped, forward pass,
   fou, freak, freaked-out, freakish, fruitcakey, fruity, funny, gaga,
   goofy, harebrain, haywire, heave, hermit, hobo, hurl, idiocratic,
   idiosyncratic, idiot, incurve, irregular, just plain nuts, kinky,
   knuckleball, kook, kooky, lateral, lateral pass, lob, lone wolf,
   loner, loon, loony, loopy, lunatic, madman, maggoty, maniac,
   maverick, meshuggenah, natural, noncompos, nonconformist, nut,
   nuts, nutty, odd, odd fellow, oddball, oddity, off the hinges,
   off the track, off the wall, original, outcurve, outsider, pariah,
   pass, peculiar, peg, phrenetic, pitch, potty, put, queer,
   queer duck, queer fish, queer specimen, quirky, rara avis,
   raving lunatic, recluse, round the bend, screwballs, screwy, serve,
   service, shot-put, shy, singular, sinker, slaphappy, slider, sling,
   solitary, spitball, spitter, strange, strange duck, throw, toss,
   tramp, twisted, type, unconventional, unnatural, upcurve, wacky,
   weirdo, whimsical, zealot

Screwball >> S Words
Screwball, definition of term: Screwball
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