peninsular, n. — Green’s Dictionary of Slang

peninsular n.

[? play on SE peninsular, a projecting strip of land, i.e. she sticks out a finger either for thieving or for emphasis]

1. a female pickpocket.

1859, 1860		Hotten Dict. of Modern Sl. etc.
1864, 1867, 1870		Hotten Sl. Dict.

2. a very inquisitive woman.

1984

Partridge DSUE (8th edn) 867: [...] since ca. 1955.