2. Pertaining to, or causing the shedding of tears.
A lachrymatory agent or lachrymator is a chemical compound that irritates the eyes to cause tears, pain, and even temporary blindness.
Tear gas and pepper spray are lachrymatory agents that are also used as riot control elements and chemical warfare agents.
Certain lachrymatory agents are often used by the police to assist in controlling offenders, most notably "tear gas" and "mace".