微扰展开 wēirǎozhǎnkāi perturbative expansion Origin Definitions Defs Strokes Stroke Words Sentences Sents 微扰 微擾 wēirǎo perturbation a small disturbance or perturbation in physics展开 展開 zhǎnkāi verb + particle to unfold To spread out or open up something folded or rolled up; to expand.