Green’s Dictionary of Slang

a derog. title put before a man’s name to imply his homosexuality.

1934		H. Sebastian ‘Negro Sl. in Lincoln University’ in AS IX:4 288: ma (also mother). An effeminate male. Usually used in lieu of a first name, as Ma Smith.
1941		G. Legman ‘Lang. of Homosexuality’ Appendix VII in Henry Sex Variants.
1965		Guild Dict. Homosexual Terms 29: ma (adj.): Uncomplimentary ‘title’ used before a male homosexual’s name, as used by heterosexuals. (Rare; now obsolete.).
1972		B. Rodgers Queens’ Vernacular 129: ma title before the surname; in most cases, Ma indicates a fuddyduddy spoil-sport.