
That's tissue inflammation.
It's a REACTION to your radiotherapy.
Breaking Bad Season 2, Episode 9

This isn't the REACTION
I expected
The Big Bang Theory Season 5, Episode 5

For every action,
there's an equal and opposite REACTION.
The Big Bang Theory Season 2, Episode 22

in which I looked up
the REACTION rates
The Big Bang Theory Season 7, Episode 6

Yeah, my initial REACTION is no.
The Big Bang Theory Season 2, Episode 22