opportunist
adjective(also opportunistic)
[usually before noun] (often disapproving)making use of an opportunity, especially to get an advantage for yourself; not done in a planned way 机会主义的;投机的;见风转舵的 an opportunist crime 临时起意的偶发犯罪 Smith marked his debut match with an opportunist goal. 史密斯以一个机会主义的进球结束了他的首场比赛。
Word Originlate 19th cent.: from opportune + -ist.