Green’s Dictionary of Slang

1. (US) the town of Tijuana, Mexico [lit. translation of Sp. tía, aunt + juana, Jane].

1928

M.C. Sharpe Chicago May (1929) 262: Aunt Jane — Tia Juana, Mex.

2. (US) menstruation.

1948

Word 4 183: Female anthropomorphisms . . are numerous: . . little sister’s here, Aunt Jane, my country cousin, I expect a visit from my Aunt Susie, are some of the more typical phrases.

3. (US black) a subservient, obsequious black woman [generic use of proper name].

1967		Wentworth & Flexner DAS (Supplement).
1972		D. Claerbaut Black Jargon in White America 57: Aunt Janen. 1. a black female who is a traitor to her race. 2. a black woman who tries to live a white life style.

4. (US black) a black woman whose world is defined by spiritual rather than secular values; a regular church-goer and religious believer [generic use of proper name].

1970

Time 6 Apr. 71: Aunt Janes [...] Affectionate black-church term for the amen-saying, clapping, lustily singing black-church ‘sister’.