facialis phenomenon

fa·ci·a·lis phe·nom·e·non

facial spasm produced by light rubbing of the skin or a tap on the zygoma; sometimes percussion above the zygoma causes contraction of the lip only; observed in tetany and sometimes in exophthalmic goiter.

fa·ci·a·lis phe·nom·e·non

(fāshē-ālis fĕ-nomĕ-nŏn)
Facial spasm produced by light rubbing of skin or tapping on the zygoma.