Definition of parasitic in US English:



  • 1(of an organism) living as a parasite.

    ‘mistletoe is parasitic on trees’
    • ‘Since viruses are parasitic on cellular life, the first life could not have been anything like a virus.’
    • ‘I never knew that mistletoe was a parasitic plant that grew off a host tree.’
    • ‘Many parasitic insects lay their eggs in fertilized ovules so that their young can feed on the starches, fats, and proteins within.’
    • ‘In vitro infection of host roots by differentiated calli of the parasitic plant Orobanche was also achieved in O. ramosa.’
    • ‘Nevertheless, growing these parasitic plants in vitro is difficult, because of their dependence on a connection to hosts for normal development, and because of their specific germination requirements.’
    • ‘Genetic parentage analyses provide a powerful approach to answering a variety of questions about parasitic birds.’
    • ‘For example, in some of the parasitic species, the males infiltrate ants while the females take up residence in grasshoppers.’
    • ‘They say that the parasitic plant which grows on nettles is nationally scarce and grows on only 100 sites across the country.’
    • ‘In place of pesticides, organic growers employ biological controls such as predatory and parasitic insects and bacteria, all of which effectively control pests in growing flowers.’
    • ‘The Bronzed Cowbird is an obligate brood parasitic species of songbird, ranging from the southern border region of the United States as far south as Central America.’
    • ‘His most influential and widely cited works concern the interactions between parasitic birds and their hosts, in particular the evolution of host defenses to brood parasitism.’
    • ‘Cowbird nestlings were placed into nests prior to the hatching of host nestlings to simulate the shorter incubation periods characteristic of parasitic species.’
    • ‘Some facultative parasitic plants such as Rhinanthus minor appear to have functional photosynthetic apparatus and can grow without a host providing reduced carbon.’
    • ‘In addition, Emberizids are hosts for brown-headed cowbirds, a parasitic species of bird that lays its eggs in the nests of other bird species.’
    • ‘For example, have allopatric populations of a parasitic species independently evolved egg or nestling mimicry of the same host species?’
    • ‘While Epifagus and Orobanche totally lack chlorophyll and therefore photosynthetic ability, there are some genera of parasitic plants that appear to be in the process of losing the ability to photosynthesize.’
    • ‘Some species are parasitic on insects, plants and animals, including man.’
    • ‘Moreover, females with two parasitic species laid eggs later than those with only one parasitic species.’
    • ‘The microorganisms that Werren studies are parasitic bacteria that survive by changing the reproductive process in their hosts.’
    • ‘We had to prune off the clade that includes all parasitic species from the tree before the analysis.’
    1. 1.1 Resulting from infestation by a parasite.
      ‘mortality from parasitic diseases’
      • ‘If parasites - or their eggs - are seen when a smear of stool is examined under the microscope, the child will be treated for a parasitic infestation.’
      • ‘And certainly in developed countries there are plenty of cases of bacterial and viral, and parasitic disease that cannot be adequately described and explained at the time it occurs.’
      • ‘Since then almost 30 years have passed and it is learnt that the control of parasitic diseases require sustained efforts from all partners.’
      • ‘The most common symptoms encountered in patients with eosinophilia were fatigue, diarrhea, or skin lesions suspicious for parasitic infection.’
      • ‘We're talking here about a parasitic disease, so this is not a bacterium or a virus, it's a parasite that goes through different life cycles.’
      • ‘On the other hand, pathological conditions are marked by gall-like swellings and vermiform borings on exoskeletons that are thought to have been caused by diseases or parasitic infestation.’
      • ‘Let's now turn our attention to the subject of parasitic infestations of the CNS.’
      • ‘Malnutrition, parasitic infestations, maternal and child morbidity and drug abuse are more important priorities and reflect on the allocation of resources for mental health services.’
      • ‘It therefore becomes enlarged in some infective, parasitic, and blood diseases.’
      • ‘I suspect that their electronic ‘portfolio’ of clinical questions would be more useful than sitting through conferences on parasitic diseases.’
      • ‘The goal of this study is to identify key environmental changes resulting from urbanization that influence outbreaks of parasitic diseases.’
      • ‘An estimated 6 million people worldwide have taken ivermectin for various parasitic infestations.’
      • ‘Public health agencies focused their activities on infectious diseases, especially vaccine preventable and endemic parasitic diseases.’
      • ‘Scabies and lice are examples of parasitic infestations.’
      • ‘It is a protozoal parasitic disease prevalent worldwide, its prevalence varying according to dietary preferences in any country.’
      • ‘Although older texts emphasized parasitic infestation, this is a rare cause of pruritus ani except for pinworms in children.’
      • ‘Scabies is a contagious parasitic infection caused by infestation of the Sarcoptes scabiei var hominis mite.’
      • ‘Of all the parasitic diseases, leishmaniasis is considered the most likely to succumb to vaccination.’
      • ‘It is essential to consider both operational and economic feasibility of any intervention to control parasitic diseases apart from its effectiveness so as to make decisions more rationally.’
      • ‘She has been involved with research and clinical aspects of the immunodiagnosis of parasitic diseases for 35 years.’
    2. 1.2derogatory Habitually relying on or exploiting others.
      ‘attacks on the parasitic existence of Party functionaries’
      • ‘It also details the parasitic activities of individual officials who live a relatively privileged existence based on extortion, bribery and other forms of corruption.’
      • ‘One explanation for the existence of parasitic mating tactics may be that dominant males exclude subordinate males from using the bourgeois mating tactic.’
      • ‘His parasitic exploitation of Ella does not stop until she is completely drained of memory, language, and finally, sanity.’
      • ‘Universities are economically parasitic, relying on external support.’
      • ‘Brahmins began to be described as cunning, parasitic exploiters and authors of the iniquitous caste system.’
      • ‘Political blogs need the press; they are parasitic on the flow of news.’
      • ‘Wages could also be higher than elsewhere in the economy as the bloodsucking, parasitic capitalist is not there demanding his piece of the action.’
      • ‘Fourthly, there has been extensive debate as to whether it is liberalism that generates the peace or whether, in a reversal of the causal chain, liberalism is parasitic upon the peace that is already in existence.’
      • ‘We can have many reasons for our conservational efforts - not all of which are parasitic on our own living standards and some of which turn precisely on our sense of values and of fiduciary responsibility.’
      • ‘At the same time, the parasitic state-owned enterprises continue to suck the blood out of the economy.’
      • ‘The lawyers, often personal injury lawyers, are jolted out of their parasitic and banal existence by the novelty of an innocent and deserving client.’
      • ‘The second myth The Economist wanted do dispel was the misapprehension that blogs are essentially parasitic on other media.’
      • ‘Even telemarketers aren't so parasitic, though their intrusiveness is often considered worse.’
      • ‘One of the many things the film is about is the essentially parasitic relationship that writers have with their subjects.’
      • ‘He and Carlyle relied heavily on the parasitic rhetoric.’
      • ‘After the princes and their state had subordinated the church, sometimes in violent conflicts, it was allowed to keep its privileged and parasitic existence.’
      • ‘Such music fests do not exist outside of a parasitic capitalist and Mafia-styled exploitive capitalist paradigm that is financed by the American government with American tax payer money.’
      • ‘Revisionism is an historical discipline made necessary by the fact that all States are governed by a ruling class that is a minority of the population, and which subsists as a parasitic and exploitative burden upon the rest of society.’
      • ‘In other words, the profits obtained by these institutions are the result of essentially parasitic activity.’
      exploitative, parasitical
      View synonyms
    3. 1.3Phonetics (of a speech sound) inserted without etymological justification (e.g., the b in thimble); epenthetic.


Early 17th century: via Latin from Greek parasitikos, from parasitos ‘(person) eating at another's table’.