tear gas

Short definition from Wiktionary

Noun

1. 1
   Any lachrymatory, non-lethal chemical compound that causes the eyes to sting and water and/or irritates the respiratory system, mostly used for controlling crowds during riots or as self-defense.
2. 2
   Alternative spelling of tear gas.

Verb

1. 1
   To use tear gas.
2. 2
   Alternative spelling of tear gas.