MAY Antonyms There are 2 antonyms of the word may. (opposite meanings)Did you mean?Definition of MAYSynonyms of MAYBest Opposite Words For MAYTop 20Top 10 Top 20 (Default)Top 50 Top 100 All All (Default)WordsPhrases All All (Default)Verb Noun Adjective Adverb RankWordSave?Synonyms..UsageType1mustverbv2cannotadverbadv Alternatives for MUST Words (14)imperativecompulsorycrucialessentialmandatorynecessaryneededobligatedprerequisiterequiredrequisitevitalmoldinessmustinessOpposite words for must Alternatives for CANNOT Words (5)impotentincapableineptpowerlessunableOpposite words for cannot