minor tranquilizer vs minor tranquilliser

minor tranquilizer and minor tranquilliser both are nouns.

Word	Noun	Adjective	Verb	Adverb
minor tranquilizer	Yes	No	No	No
minor tranquilliser	Yes	No	No	No

As nouns, minor tranquilizer and minor tranquilliser are synonyms defined as:

minor tranquilizer and minor tranquilliser: a tranquilizer used to relieve anxiety and reduce tension and irritability

Other synonyms of minor tranquilizer include antianxiety drug, anxiolytic, anxiolytic drug, minor tranquillizer.

minor tranquilizer (noun)	minor tranquilliser (noun)
a tranquilizer used to relieve anxiety and reduce tension and irritability	a tranquilizer used to relieve anxiety and reduce tension and irritability