One who takes advantage of any opportunity to achieve an end, often with no regard for principles or consequences.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "opportunist" in a sentence
"Charlie Crist, battered by rivals as a political opportunist, is losing ground in his quest to build a bipartisan voter coalition and win a U.S."
"Has here ever been a more blatant opportunist is U.S. politics?"
"And, if that happens, can he be confident of carrying the army and his rag-tag opportunist supporters with him?"