Definify.com

Webster 1913 Edition

(păr′ȧ-sīˊtĭz’m; 277)

Noun.

[Cf. F.

parasitisme

The state or behavior of a parasite; the act of a parasite.

“Court parasitism.”

Milton.

(Bot. & Zool.)

The state of being parasitic.

Noun.

The behavior or manners of a parasite.

parasitism ‎(usually uncountable, plural parasitisms)

(ecology) Interaction between two organisms, in which one organism (the parasite) benefits and the other (the host) is harmed.
(figuratively) A similar interaction between people.
We accused her of parasitism in taking his hard-earned money for new dresses.

interaction between two organisms