"Frenemy" (alternately spelled "frienemy") is a portmanteau of "friend" and "enemy" that can refer to either an enemy pretending to be your friend or someone who really is your friend but is also a rival. The term is used to describe personal, geopolitical, and commercial relationships both among individuals and groups or institutions. The word has appeared in print as early as 1953.
A Businessweek article stated that frenemies in the workplace are common, due to increasingly informal environments and the "abundance of very close, intertwined relationships that bridge people's professional and personal lives ... [while] it certainly wasn't unheard of for people to socialize with colleagues in the past, the sheer amount of time that people spend at work now has left a lot of people with less time and inclination to develop friendships outside of the office."
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