opportunistic

adjective

op·​por·​tu·​nis·​tic ˌä-pər-tü-ˈni-stik 

-tyü-

: 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

opportunistically

ˌä-pər-tü-ˈni-sti-k(ə-)lē 

-tyü-

adverb

Examples of opportunistic in a Sentence

Recent Examples on the Web

Over the last 50 years, opportunistic pathogens have evolved defenses faster than humans can develop drugs to combat them. —Tribune News Service, The Mercury News, 18 May 2024

Some opportunistic investors have bought bankruptcy claims from the exchange’s customers for pennies on the dollar, hoping to profit when the payouts begin. —David Yaffe-Bellany, New York Times, 8 May 2024

Word History

Etymology

opportunist + -ic entry 1

First Known Use

1892, in the meaning defined above

Kids Definition

opportunistic

noun

op·​por·​tu·​nis·​tic -t(y)ü-ˈnis-tik 

: taking advantage of opportunities as they arise: as

a

: exploiting opportunities with little regard to principle or consequences

an opportunistic cheater

b

: feeding on whatever food is available

opportunistic feeders

Medical Definition

opportunistic

adjective

op·​por·​tu·​nist·​ic -t(y)ü-ˈnis-tik 

1

: of, relating to, or being a microorganism that is usually harmless but can become pathogenic when the host's resistance to disease is impaired

2

: of, relating to, or being an infection or disease caused by an opportunistic organism

Pneumocystis carinii pneumonia and other opportunistic infections that kill AIDS patients

—New York Times