Meaning of “flicker” - Learner’s Dictionary

flicker

verb [ I ] us uk /ˈflɪkər/
SHINE

to shine with a light that is sometimes bright and sometimes weak:

A candle flickered in the window.
APPEAR

to appear for a short time or make a sudden movement somewhere:

A smile flickered across her face.

(Definition of “flicker verb” from the Cambridge Learner’s Dictionary © Cambridge University Press)