temblar

to tremble, to quiver, to quake, to shudder, to cringe, to quail; to shake; to shiver; to twitch

Inherited from Old Spanish temblar, tembrar, from an original trembrar (via dissimilation), from Late Latin tremulāre, a verb based on Classical Latin tremulus (“quivering”), from tremere (“tremble”). Doublet of tremolar.