Definition of opportunistic
: taking advantage of opportunities as they arise: such as
a
: exploiting opportunities with little regard to principle (see principle sense 1) or consequences
a politician considered opportunistic an opportunistic investment
b
: feeding on whatever food is available
opportunistic feeders opportunistic bears
c
: being or caused by a usually harmless microorganism that can become pathogenic when the host's resistance is impaired
opportunistic infections opportunistic diseases
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Time Traveler for opportunistic
The first known use of opportunistic was in 1892
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