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

What’s really happening is that Toto made a timely — if opportunistic — play into the space around AI chip manufacturing. —Joe Wilkins, Futurism, 4 June 2026

The organisers can be international crime conglomerates or opportunistic chancers, its markets veering from last-minute own goals to a couple of extra throw-ins. —Jacob Whitehead, New York Times, 4 June 2026

Information about treatments for the many opportunistic infections that HIV made people vulnerable to was gathered in the early years by those under threat. —Liz Tracey, JSTOR Daily, 3 June 2026

The company’s opportunistic share repurchases, including a $1 billion increase to its buyback authorization in February, didn’t help the stock. —Jeff Marks, CNBC, 2 June 2026

Word History

Etymology

opportunist + -ic entry 1

First Known Use

1892, in the meaning defined above

Rhymes for opportunistic

• anachronistic
• animalistic
• antagonistic
• antiphlogistic
• behavioristic
• cannibalistic
• capitalistic
• characteristic
• collectivistic
• deterministic
• ethnolinguistic
• expressionistic

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