MEANING: noun:
1. A series of events, each triggered or influenced by the previous.
2. A chemical or nuclear reaction that results in products that cause further reactions

ETYMOLOGY: From chain, from Old French chaine/chaeine, from Latin catena (chain) + act, from Latin actus (act). Earliest documented use: 1926.

CHAI REACTION - being allergic to spiced Russian tea

CHAIN REDACTION - a panel of editors makes one change after another

CHIN REACTION - Tinea barbae [a skin condition on the face, from using the wrong kind or razor or having the wrong kind of beard. YCLIU.]