parasite
Lives off others
A parasite is an organism that lives on or inside another organism, called the host, from which it obtains nutrients while providing no benefit in return and often causing harm.
Fleas, tapeworms, and mistletoe are all parasites.
The word extends readily to people who exploit others' generosity or resources without contributing anything: He's been a parasite on his parents for years.
The adjective parasitic describes this relationship in both biological and figurative contexts.
Organism feeding on plasma
- leechBlood-feeding aquatic worm
- vultureCarrion-eating raptor
- bottom-feederCreature eating from below
- scumSurface residue or lowlifes
lowlife · user · exploiter · sycophant · toady · gold-digger · grifter · con-artist
One exploiting others' generosity
- moocherOne who cadges habitually
- spongerOne who mooches
- leechBlood-feeding aquatic worm
- dependentRequiring outside support
exploiter · user · hanger-on · deadbeat · scrounger · layabout · opportunist · burden
One receiving guests
- infectionPathogen invasion causing illness
- pathogenDisease-causing microorganism
- vectorQuantity with direction
- transmissionSending of information
life-cycle · infestation · larva · eggs · reproduction · virulence · endoparasite · ectoparasite
Parasitic eight-legged pest
- fleaBlood-drinking jumping pest
- louseWingless biting parasite
- miteMinuscule arachnid parasite
- bedbugBlood-sucking mattress dweller
mosquito · chigger · botfly · screwworm · tsetse · blood-feeding · bite · itch
Organism feeding on plasma
- annelidSegmented worm phylum member
- anticoagulantSubstance preventing blood clots
- medicinalHaving healing properties
- aquaticWater-inhabiting
suction · segmented · phlebotomy · swamp · pond · attachment · detach · engorged
Interspecies biological interdependence
- commensalismNeutral host, benefiting guest
- mutualismTwo-way biological benefit
- hostOne receiving guests
- coevolutionReciprocal adaptation between interacting species
predator · prey · niche · adaptation · fitness · exploitation · cuckoo · cowbird
Encroaching without welcome
- unwantedNot wished for
- infestationPest takeover situation
- infiltratorOne who enters covertly
- alienNon-native being
foreign · intrusion · encroacher · uninvited · opportunistic · colonizer · invader · contamination
Mosquito-borne parasitic infection
- infectionPathogen invasion causing illness
- tropicalOf hot, humid regions
- epidemicWidespread disease occurrence
- dysenteryBloody intestinal infection
leishmaniasis · elephantiasis · toxoplasmosis · giardiasis · trichinosis · hookworm · pinworm · ivermectin
Two-way biological benefit
- commensalismNeutral host, benefiting guest
- lichenSymbiotic rock dweller
- coralMarine skeletal formation
- oxpeckerParasite-eating African bird
bloodsucker
Organism feeding on plasma
- leechBlood-feeding aquatic worm
- vultureCarrion-eating raptor
- bottom-feederCreature eating from below
scum · lowlife · user · exploiter · sycophant · toady · gold-digger · grifter · con-artist · freeloader
freeloader
One exploiting others' generosity
dependent · exploiter · user · hanger-on · deadbeat · scrounger · layabout · opportunist · burden · drain
host
One receiving guests
- infectionPathogen invasion causing illness
- pathogenDisease-causing microorganism
- vectorQuantity with direction
transmission · life-cycle · infestation · larva · eggs · reproduction · virulence · endoparasite · ectoparasite · nematode
tick
Parasitic eight-legged pest
bedbug · mosquito · chigger · botfly · screwworm · tsetse · blood-feeding · bite · itch · infestation
bloodsucker
Organism feeding on plasma
- annelidSegmented worm phylum member
- anticoagulantSubstance preventing blood clots
- medicinalHaving healing properties
aquatic · suction · segmented · phlebotomy · swamp · pond · attachment · detach · engorged · saliva
symbiosis
Interspecies biological interdependence
- commensalismNeutral host, benefiting guest
- mutualismTwo-way biological benefit
- hostOne receiving guests
coevolution · predator · prey · niche · adaptation · fitness · exploitation · cuckoo · cowbird · mimicry
invasive
Encroaching without welcome
- unwantedNot wished for
- infestationPest takeover situation
- infiltratorOne who enters covertly
alien · foreign · intrusion · encroacher · uninvited · opportunistic · colonizer · invader · contamination · spread
malaria
Mosquito-borne parasitic infection
- infectionPathogen invasion causing illness
- tropicalOf hot, humid regions
- epidemicWidespread disease occurrence
dysentery · leishmaniasis · elephantiasis · toxoplasmosis · giardiasis · trichinosis · hookworm · pinworm · ivermectin · treatment
mutualism
Two-way biological benefit
- commensalismNeutral host, benefiting guest
- lichenSymbiotic rock dweller
- coralMarine skeletal formation
oxpecker · clownfish · interdependence · coexistence · microbiome
- life formsorganisms, organism, lifeforms, animal, creatures
- para- wordsparachute, paragraph, parallel, paramedic, paradise
- Malariamalaria, vivax, Anopheles, mosquito, antimalarial
- Pathogenspathogen, germ, germs, bacteria, bacterium
- freeloadersfreeloader, mooch, moocher, sponge, sponger
- hangers-onhanger-on, tagalong, leech, freeloader, sponger
parasitemutualist
Partner in mutual benefit
symbiote · commensal · host · pollinator · cleaner fish
parasitebenefactor
One who gives aid
philanthropist · producer · contributor · giver · supporter
parasiteindependent
Free from external control
self-sufficient · self-reliant · earner · worker · hard worker
- parasitic relationshipOne organism drains another
- parasitic diseaseCondition caused by host-dependent organisms
- brain parasitesOrganisms infesting brain tissue
- intestinal parasitesOrganisms infesting digestive tract
- parasitic wormsOrganisms inhabiting host bodies
- brood parasiteSpecies using others' nests
brood parasite, obligate parasite, parasitic, parasites, parasitism, parasitize, parasitical, parasitology, parasitized