WordWeb Online

1. An animal or plant that lives in or on a host (another animal or plant); it obtains nourishment from the host without benefiting or killing the host
    
2. A follower who hangs around a host (without benefit to the host) in hope of gain or advantage
   - leech, sponge [informal], sponger, bloodsucker [informal]
    
3. A person or organization that extracts resources or money without providing any useful contribution
   "Wall Street speculators are a parasite on the real economy"

Derived forms: parasites

Type of: acolyte, being, follower, organism

Antonym: host

Encyclopedia: Parasite