The Collaborative International Dictionary of English v.0.48:

Diddle \Did"dle\, v. i. [Cf. Daddle.]
   To totter, as a child in walking. [Obs.] --Quarles.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Diddle \Did"dle\, v. t. [Perh. from AS. dyderian to deceive, the
   letter r being changed to l.]
   To cheat or overreach. [Colloq.] --Beaconsfield.
   [1913 Webster]

WordNet (r) 3.0 (2006):

diddle
    v 1: deprive of by deceit; "He swindled me out of my
         inheritance"; "She defrauded the customers who trusted
         her"; "the cashier gypped me when he gave me too little
         change" [syn: victimize, swindle, rook, goldbrick,
         nobble, diddle, bunco, defraud, scam, mulct,
         gyp, gip, hornswoggle, short-change, con]
    2: manipulate manually or in one's mind or imagination; "She
       played nervously with her wedding ring"; "Don't fiddle with
       the screws"; "He played with the idea of running for the
       Senate" [syn: toy, fiddle, diddle, play]

The Free On-line Dictionary of Computing (19 January 2023):

diddle

    (US) To work in a casual manner, or the result of such
   work.  (In the UK "to diddle someone" means to cheat them).

   "I diddled a copy of ADVENT so it didn't double-space all the
   time."  "Let's diddle this piece of code and see if the problem
   goes away."

   Similar to twiddle, less purposeful than tweak.

   [Jargon File]

   (2013-08-18)


The Jargon File (version 4.4.7, 29 Dec 2003):

diddle


    1. vt. To work with or modify in a not-particularly-serious manner. “I
    diddled a copy of ADVENT so it didn't double-space all the time.” “Let's
    diddle this piece of code and see if the problem goes away.” See tweak
    and twiddle.

    2. n. The action or result of diddling.

    See also tweak, twiddle, frob.