lachrymator vs CN gas

lachrymator and CN gas both are nouns.

Word	Noun	Adjective	Verb	Adverb
lachrymator	Yes	No	No	No
CN gas	Yes	No	No	No

As nouns, CN gas is a hyponym of lachrymator; that is, CN gas is a word with a more specific, narrower meaning than lachrymator:

lachrymator: a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds
CN gas: a tear gas that is weaker than CS gas but lasts longer

Other hyponyms of lachrymator include chlorobenzylidenemalononitrile, CS gas, chloroacetophenone, nitrochloromethane.

lachrymator (noun)	CN gas (noun)
a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds	a tear gas that is weaker than CS gas but lasts longer