The Collaborative International Dictionary of English v.0.48:
Opportunist \Op`por*tun"ist\, n. [Cf. F. opportuniste.] One who advocates or practices opportunism. [Recent] [1913 Webster]WordNet (r) 3.0 (2006):
opportunist adj 1: taking immediate advantage, often unethically, of any circumstance of possible benefit [syn: opportunist, opportunistic, timeserving] n 1: a person who places expediency above principle [syn: opportunist, self-seeker]