verb

(of light or a source of light) shine unsteadily; vary rapidly in brightness.

the interior lights flickered, and came on

glimmer,glint,gleam,flare,shine,dance,gutter,twinkle,sparkle,blink,wink,flash,scintillate,glisten,shimmer,glitter,glister,coruscate,fulgurate,effulge

noun

an unsteady movement of a flame or light causing rapid variations in brightness.

the flicker of a candle flame caught our eyes