What does parasitic mean?
Parasitic describes something that lives on, in, or alongside another organism and benefits at that organism’s expense. In biology, the term applies to organisms such as parasitic wasps, plants, and microorganisms, while in everyday use it can describe exploitative behavior, such as relying unfairly on another person or organization. The adjective also conveys the broader idea of dependence that resembles parasitism. Although parasitic relationships are sometimes discussed alongside symbiotic relationships, “parasitic” normally implies that the parasite benefits while the host is harmed or disadvantaged. Understanding the word helps distinguish genuine biological interdependence from relationships that are one-sided and potentially damaging.
Of or relating to an organism that lives on or in a host and obtains benefit at the host’s expense; living in such a way.
"The parasite was found to be a parasitic species of wasp."
Exploitative, unfairly dependent on another person or organization, or characterized by such dependence.
"The arrangement was parasitic, allowing the larger company to profit while the workers received very little."
An organism that lives on or in a host and obtains nourishment or other benefits at the host’s expense.
"The specimen was a parasitic adapted to life inside its host."
The word comes from Greek parasitos, literally “one who eats beside another,” a fittingly vivid description of the original parasitic custom.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does parasitic come from?
The word comes through Latin from Greek parasitos, a term for someone who eats beside another and lives at another person’s expense. The sense of an organism depending on a host developed from that older social and culinary metaphor. English borrowed the term in the 16th century in medical and biological writing, and it was later extended figuratively to exploitative or unfairly dependent behavior.
Related word forms
How parasitic is actually used
In biological contexts, “parasitic” is a technical term for an organism that lives on or in a host. In social and economic contexts, it is commonly metaphorical and implies exploitation or unfair dependence, often with a critical or disapproving tone.
Easily confused with parasitic
A parasite is the organism that lives on or in a host, while parasitic is the adjective describing that organism or its behavior.