PARASITE
parasite
(noun) 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
leech, parasite, sponge, sponger
(noun) a follower who hangs around a host (without benefit to the host) in hope of gain or advantage
Source: WordNet® 3.1
Etymology
Noun
parasite (plural parasites)
(pejorative) A person who lives on other people's efforts or expense and gives little or nothing back. [from 16th c.]
(pejorative) A sycophant or hanger-on.
(biology) An organism that lives on or in another organism of a different species, deriving benefit from living on or in that other organism, while not contributing towards that other organism sufficiently to cover the cost to that other organism.
(literary, poetic) A climbing plant which is supported by a wall, trellis etc. [from 19th c.]
(historical) A retainer or companion of an ancient Celtic warrior, who praised him in song or poetry at gatherings; a bard.
Synonyms
• (useless person): See also scrounger
Antonyms
• commensal (doing no noticeable harm)
• mutualist or sometimes symbiote (beneficial)
Anagrams
• aspirate, pastiera, septaria
Source: Wiktionary
Par"a*site, n. Etym: [F., fr. L. parasitus, Gr.
1. One who frequents the tables of the rich, or who lives at
another's expense, and earns his welcome by flattery; a hanger-on; a
toady; a sycophant.
Thou, with trembling fear, Or like a fawning parasite, obey'st.
Milton.
Parasites were called such smell-feasts as would seek to be free
guests at rich men's tables. Udall.
2. (Bot.)
(a) A plant obtaining nourishment immediately from other plants to
which it attaches itself, and whose juices it absorbs; -- sometimes,
but erroneously, called epiphyte.
(b) A plant living on or within an animal, and supported at its
expense, as many species of fungi of the genus Torrubia.
3. (Zoöl.)
(a) An animal which lives during the whole or part of its existence
on or in the body of some other animal, feeding upon its food, blood,
or tissues, as lice, tapeworms, etc.
(b) An animal which steals the food of another, as the parasitic
jager.
(c) An animal which habitually uses the nest of another, as the
cowbird and the European cuckoo.
Source: Webster’s Unabridged Dictionary 1913 Edition