Noun

(en noun)

A state of turbulent motion.

An agitated disturbance or a hubbub.

* {{quote-book, year=1963, author=(Margery Allingham), title=(The China Governess)

, chapter=19 citation , passage=When Timothy and Julia hurried up the staircase to the bedroom floor, where a considerable commotion was taking place, Tim took Barry Leach with him. He had him gripped firmly by the arm, since he felt it was not safe to let him loose, and he had no immediate idea what to do with him.}}

(euphemistic) Sexual excitement.

{{quote-Fanny Hill, part=3 , and now, glancing my eyes towards that part of his dress which cover'd the essential object of enjoyment, I plainly discover'd the swell and commotion there}}

Noun

(en noun)

An action or statement in response to a stimulus or other event

The announcement of the verdict brought a violent reaction .

You were in the courtroom. What is your reaction ?

When I last tried to eat strawberries I had a terrible allergic reaction .

(chemistry) A transformation in which one or more substances is converted into another by combination or decomposition

In this reaction , the acid and base will neutralize each other, producing a salt.