react has definitions from the field of chemistry
1
[ verb ] show a response or a reaction to something

Synonyms

respond

Used in print

(St. Louis Post-Dispatch,...)

The truth is , though , that men react differently to different treatment .

(Edward E. Kelly, S.J., "Christian Unity in England"...)

English Catholics reacted to this event with moderate but real hope .

(High Fidelity, 11:10...)

Those accustomed to broader , more romantic statements of the symphony can be expected to react strongly when they hear this one .

(Clement Greenberg, "Collage" in his Art and...)

Depicted , Cubist flatness is now almost completely assimilated to the literal , undepicted kind , but at_the_same_time it reacts upon and largely transforms the undepicted kind - and it does so , moreover , without depriving the latter of its literalness ; rather , it underpins and reinforces that literalness , re-creates it .

2
[ verb ] act against or in opposition to

Synonyms

oppose

Examples

"She reacts negatively to everything I say"

Used in print

(Max F. Millikan and Donald L. M. Blackmer,...)

We should do what we can to discourage this conclusion , both by offering assistance for their domestic needs and by reacting firmly to irresponsible actions on the world scene .

Related terms

act pursue buck backfire adversary

3
[ verb ] (chemistry) undergo a chemical reaction; react with another substance under certain conditions

Examples

"The hydrogen and the oxygen react"

Used in print

(Jay C. Harris and John R. Van Wazer, "Detergent...)

Greasy soils are hardly removed by washing in plain water ; and natural waters , in_addition , often contain impurities such_as calcium salts which can react with soils to make them more difficult to remove .

(A. N. Nagaraj and L. M. Black, "Localization of...)

After blotting_out most of the saline around the sections , a drop of * * f was layered over each of the sections , allowed to react for 30_minutes , and then washed with PBS for 15 - 30_minutes .

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