Is “React” a Scrabble word?

1.An emoji used to express a reaction to a post on social media.

“Sad reacts only”

1.To act or perform a second time; to do over again; to reenact.

2.To return an impulse or impression; to resist the action of another body by an opposite force

“Every body reacts on the body that impels it from its natural state.”

3.To act upon each other; to exercise a reciprocal or a reverse effect, as two or more chemical agents; to act in opposition.