Dictionary.com
Thesaurus.com
Showing results for reactivity. Search instead for web activity.
Synonyms

reactivity

American  
[ree-ak-tiv-i-tee] / ˌri ækˈtɪv ɪ ti /

noun

  1. the quality or condition of being reactive.

  2. Chemistry. the relative capacity of an atom, molecule, or radical to undergo a chemical reaction with another atom, molecule, or compound.

  3. Physics. a measure of the deviation from the condition at which a nuclear reactor is critical.

  4. Immunology. the ability of an antigen to combine with an antibody.


Other Word Forms

Etymology

Origin of reactivity

First recorded in 1885–90; reactive + -ity

Vocabulary lists containing reactivity

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The study found that the change in reporting dramatically reduced investors’ reactivity to market volatility, and a corresponding increase in their willingness to invest in riskier funds.

From MarketWatch • May 2, 2026

Paris police chief Patrice Faure paid tribute to "the reactivity and the mobilisation" of the investigators that led to the arrest of the suspect.

From Barron's • Dec. 27, 2025

The team suspected that choosing the correct ligand might unlock reactivity with alkyl ketones.

From Science Daily • Nov. 26, 2025

“We told Jack we needed a special person to handle this dog,” says Padilla, referencing Felisha’s fear-based reactivity.

From Los Angeles Times • Jul. 21, 2025

Too much reactivity and we would spontaneously combust.

From "The Gene" by Siddhartha Mukherjee