Source : Webster's Revised Unabridged Dictionary (1913)

Flop \Flop\, n.
   Act of flopping. [Colloq.] --W. H. Russell.

Flop \Flop\, v. t. [imp. & p. p. {Flopped}; p. pr. & vb. n.
   {Flopping}.] [A variant of flap.]
   1. To clap or strike, as a bird its wings, a fish its tail,
      etc.; to flap.

   2. To turn suddenly, as something broad and flat. [Colloq.]
      --Fielding.

Flop \Flop\, v. i.
   1. To strike about with something broad abd flat, as a fish
      with its tail, or a bird with its wings; to rise and fall;
      as, the brim of a hat flops.

   2. To fall, sink, or throw one's self, heavily, clumsily, and
      unexpectedly on the ground. [Colloq.] --Dickens.

Source : WordNet®

flop
     adv 1: with a flopping sound; "he tumbled flop into the mud"
     2: exactly; "he fell flop on his face" [syn: {right}]
     v 1: fall loosely; "He flopped into a chair"
     2: fall suddenly and abruptly
     3: fail utterly; collapse; "The project foundered" [syn: {fall
        through}, {fall flat}, {founder}]
     [also: {flopping}, {flopped}]

flop
     n 1: an arithmetic operation performed on floating-point numbers;
          "this computer can perform a million flops per second"
          [syn: {floating-point operation}]
     2: someone who is unsuccessful [syn: {dud}, {washout}]
     3: a complete failure; "the play was a dismal flop" [syn: {bust}]
     4: the act of throwing yourself down; "he landed on the bed
        with a great flop" [syn: {collapse}]
     [also: {flopping}, {flopped}]

Source : Free On-Line Dictionary of Computing

FLOP
     
        1. An early system on the {IBM 701}.
     
        [Listed in CACM 2(5):16 (May 1959)].
     
        (1994-11-14)
     
        2. Erroneous singular of {FLOPS}.