whimwham (n.) “whimsical device, trifle,” 1520s, of unknown origin; perhaps from Scandinavian (cf. Old Norse hvima “to let the eyes wander,” Norwegian kvima “to flutter”), or else an arbitrary native formation (cf. flim-flam).
flim-flam (n.) also flimflam, 1530s, a contemptuous echoic construction, perhaps connected to some unrecorded dialectal word from Scandinavian (cf. Old Norse flim “a lampoon”). From 1650s as a verb.
The word that floated into my mind this morning was whimsical, which I always associate with lightness, fantasy and ephemeral associations of happy serendipity. The word itself is of no fixed address, as one sees from the ever-faithful OED, arriving on the wings of whimwham, evidently originating from Old Norse, which makes a nice change from Middle English (and demonstrates that you CAN teach an Old Norse new tricks). From the Norwegian kvima, to flutter, as whimsy does.
Ben Jonson used it in 1607 in Volpone:
I can feel
A whimsy in my blood: I know not how,
Success hath made me wanton.
Thus both whimsy and wantonness, heady stuff – I love the temporary temporality of whimsy as something always hovering, like the whisper of a hummingbird trembling at a flower – it captures the essence of imagination and of wonder –