WordNet (r) 3.0 (2006):

wimp
    n 1: a person who lacks confidence, is irresolute and wishy-
         washy [syn: wimp, chicken, crybaby]
    2: a hypothetical subatomic particle of large mass that
       interacts weakly with ordinary matter through gravitation;
       postulated as a constituent of the dark matter of the
       universe [syn: weakly interacting massive particle, WIMP]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

WIMP
       Window, Icon, Menu, Pointing device


The Free On-line Dictionary of Computing (30 December 2018):

WIMP
WIMP environment

    Windows, Icons, Menus and Pointers
   (or maybe Windows, Icons, Mouse, Pull-down menus).

   The style of graphical user interface invented at Xerox
   PARC, popularised by the Apple Macintosh and now available
   in other varieties such as the X Window System,
   OSF/Motif, NeWS, RISC OS and Microsoft Windows.

   See menuitis, user-obsequious, window system.

   (2007-09-12)