Green’s Dictionary of Slang

Mary n.

also Marie
[generic use of one of the most common of female proper names, but also offering a touch of Mariolatry]

1. uses based on being female.

(a) [early 19C+] (Aus./N.Z., also meri) an Aboriginal native woman; thus pidgin White Mary, a white woman.

(b) [1900s–10s] (Irish/Aus., also mary ann, mary jane) a female servant.

(c) [1900s–70s] (S.Afr., also coolie Mary) an Indian woman, usu. a fruit or vegetable hawker.

(d) [1940s+] (S.Afr.) any black woman, esp. a domestic servant.

2. (also Marjorie) gay uses.

(a) [1920s+] the most popular camp proper name; typically in phr. get you Mary!

(b) [1950s+] thus, a gay man’s (younger) lover.

(c) [2000s] (S.Afr. gay) a magistrate.

3. drug uses.

(a) [1940s–50s] (US drugs) morphine [the shared initial letter M].

(b) see mary jane n.1

(c) see mary jane n.2

In phrases

go to Mary’s room (v.) (also go to visit aunty, go to visit Mary) [euph.]

[1980s] (Aus.) to use the lavatory.