Synonyms for React:

n.

pick up on, pounce, reciprocate, receive, come back, stand up, counter, turn around and do something, come over, give back. bond, assay, balanced equation, the carbon cycle, calcify, adsorb, aerate, take, behavior, find, feel. anaphylactic shock, allergic, intolerant, hypoallergenic, anaphylaxis, action, allergen, intolerance, allergy, hypersensitive, antigen. feelings, greet, meet, greeting. react (noun)
respond, oppose.

v.

acknowledge (verb)
respond, greet.
act (verb)
execute, endeavor, DO, work, move, behave, labor, comport, act, appear, operate, exercise, perpetrate, enterprise, officiate, transact, conduct, function, perform.
boomerang (verb)
come back.
cognition (verb)
respond.
function (verb)
officiate, move.
perform (verb)
transact, meet.
react (verb)
echo, function, reciprocate, act, answer, counter, reply, work, give back, behave, perform, acknowledge, return, operate, feel, take.
respond (verb)
echo, expound, deny, answer, rebut, return, reply, object, refute, defend, explain, respond, justify, retort, acknowledge.
social (verb)
oppose.

Other synonyms:

pounce, pick up on, reciprocate. stand up. receive. greet. meet. answer
reply.
take
take.
Other relevant words:
give back, take, oppose, greet, counter, meet, reciprocate, come back, feel.

Usage examples for react

  1. That was cold tub number two for that day, and I didn't react as quickly as I might, but when I did I was in the proper glow all over. – The Melting of Molly by Maria Thompson Daviess
  2. I think that your pains now react on me, and I have a headache on account of them. – The George Sand-Gustave Flaubert Letters by George Sand, Gustave Flaubert Translated by A.L. McKensie
  3. And his very swiftness in itself would react against him, for he was continually under the temptation daily to exceed by a little his powers. – The Silent Places by Steward Edward White