minor tranquilliser vs minor tranquillizer

minor tranquilliser and minor tranquillizer both are nouns.

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

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

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

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

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