Flicker, v. i. [imp. & p. p. Flickered; p. pr. & vb. n. Flickering.]
Etymology: [OE. flikeren, flekeren, to flutter, AS. flicerian, flicorian, cf. D. flikkeren to sparkle. Flacker.]
1. To flutter; to flap the wings without flying. And flickering on her nest made short essays to sing. Dryden.
2. To waver unsteadily, like a flame in a current of air, or when about to expire; as, the flickering light. The shadows flicker to fro. Tennyson.
1 other Webster entry under this spelling
Flicker, n.
1. The act of wavering or of fluttering; flucuation; sudden and brief increase of brightness; as, the last flicker of the dying flame.
2. (Zoöl.)
The golden-winged woodpecker (Colaptes aurutus); -- so called from its spring note. Called also yellow-hammer, high-holder, pigeon woodpecker, and yucca. The cackle of the flicker among the oaks. Thoureau.
Shades of meaning
Fernald has no entry of its own for flicker; he lists it under light.
He lists it without comment; the entries above explain its neighbors.