1920 (but not attested again until 1960), perhaps a clipped form of whimper (cf whimp, 1540s), perhaps influenced by J. Wellington Wimpy, comparatively unaggressive character in "Popeye" comics.
1986, with out (adv.), from wimp (n.). Related: Wimped; wimping.
Short for weakly interacting massive particle. Any of various hypothetical particles, some predicted by certain theories such as supersymmetry, which interact with other particles by the force of gravity alone. WIMPs are considered by some scientists to be candidates for the dark matter that makes up much of the mass of the universe.
May the actual claimant now be identified: After listening to Mr. Brown and Mr. Christopher, it was tempting to ask: Would the real Secretary of Commerce please stand up?
[1950s+; fr a television panel show, To Tell the Truth, where three different people claimed to have a certain identity, and the real one was finally asked to stand up]