"whimsical device, trifle," 1520s, of unknown origin; perhaps from Scandinavian (compare Old Norse hvima "to let the eyes wander," Norwegian kvima "to flutter"), or else an arbitrary native formation (compare flim-flam).
whilst
whim
whimper
whimsical
whimsy
whimwham
whine
whiney
whinge
whinner
whinny