Green’s Dictionary of Slang

Saturday n.

SE in slang uses

In compounds

Saturday gangster (n.)

[1990s+] (Aus. Und.) an aspirant gangster.

Saturday-night (n.)

[late 19C] wages.

In phrases

Saturday-to-Monday (n.)

[1900s–10s] a mistress whom one sees only at weekends.

shitten Saturday (n.) [mispron. of SE shut-in Saturday, referring to the day on which Christ’s body was enclosed in his tomb]

[mid-19C] (mainly school/provincial) Easter Saturday.