simple past tense and past participle of twitch

A brief, small (sometimes involuntary) movement out of place and then back again; a spasm. / (informal) Action of spotting or seeking out a bird, especially a rare one.

(intransitive) To perform a twitch; spasm. / (transitive) To cause to twitch; spasm. / (transitive) To jerk sharply and briefly. / (obsolete) To exert oneself.

couch grass (Elymus repens; a species of grass, often considered as a weed)

present participle of twitch

The motion of something that twitches. / (birdwatching) Compulsive birdwatching by people (twitchers) who travel long distances to see rare species.

That twitches.

plural of twitch

Third-person singular simple present indicative form of twitch

plural of twitching