Green’s Dictionary of Slang

slang n.2

[Ger. Schlange, a chain, watch-chain or Du. slang, a snake]

1. [late 18C–1910s] any form of chains or fetters used to secure a prisoner; usu. in pl.; the noose.

2. [19C–1940s] a watch-chain.

3. [1930s] (US Und.) a necklace.

4. [1990s+] (S.Afr. gay) the penis.

In compounds

slang-dipper (n.)

[20C+] one who gilds ordinary metal chains and attempts to pass them off as ‘gold’; thus slang-dropper, the person who actually does the ‘trade’, usu. by dropping a chain in the street, picking it up as the victim is passing, then asking them to suggest how much it might be worth; they then get the dupe to buy it, assuring them that they themselves are losing by the deal.

slangpark (n.)

[1990s+] (S.Afr. gay) a public lavatory used for soliciting, a ‘cottage’.

In phrases

double-slangs (n.)

[late 18C–mid-19C] double irons; thus double-slanged, fettered on both legs.