Definition of reactive in English:

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Pronunciation: /rɪˈaktɪv/


1Showing a response to a stimulus: pupils are reactive to light
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  • Is the measles virus reactive to ultra violet light?
  • The reactive response is when my ego is offended.
  • I was a bit surprised to read the reactive / defensive response of some of my classmates.
1.1 Physiology Showing an immune response to a specific antigen: lysosomal activity can activate B lymphocytes reactive against self-components
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  • Several methods are available to prevent the formation of preformed reactive antibodies to HLA antigens.
  • Arrows indicate cells reactive to the zeatine specific antibodies.
  • Eyebright appears to make your immune system less reactive to airborne allergens.
1.2(Of a disease or illness) caused by a reaction to something: reactive arthritis reactive depression
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  • Reiter's syndrome is a form of reactive arthritis, an inflammation of the joints that occurs in response to infection.
  • The histologic causes of these false-positive lymph nodes were granuloma, reactive inflammation, and anthracosis.
  • The etiology of a pulmonary exacerbation is likely a variety of airway insults including respiratory viral infections, reactive airway disease, and pollutants.
1.3Having a tendency to react chemically: nitrogen dioxide is a highly reactive gas
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  • Ozone is produced when sunlight triggers chemical reactions involving reactive hydrocarbons and nitrogen oxides.
  • A molecule's functional group is the chemically reactive portion, or segment, of an organic chemical molecule.
  • At room temperature, formaldehyde is an extremely reactive colorless gas with a suffocating odor.
2Acting in response to a situation rather than creating or controlling it: a proactive rather than a reactive approach
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  • The leaders who built enduring great companies showed a creative inside-out approach rather than a reactive outside-in approach.
  • The key is to be proactive rather than reactive taking a firm stance before the situation gets out of hand.
  • Much of Cuba's Internet control strategy has entailed reactive state responses to the challenges outlined above.
3 Physics Relating to reactance: a reactive load
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  • It is important to remember that any reactive load will produce standing waves on the line.
  • There are separate accumulators for generator tripping and 500-kV reactive power compensation switching for this algorithm as well.
  • Generator tripping must be technically and contractually feasible, and the reactive power devices must be in place.



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