Green’s Dictionary of Slang

diesel n.

[SE diesel, a locomotive driven by a diesel engine]

1. [1970s+] (UK prison) prison tea [its taste, supposedly reminiscent of diesel fuel].

2. [1980s+] (US) one who has a muscular, well-developed physique.

3. see diesel-dyke n.

In compounds

diesel-queen (n.) [-queen sfx (2)]

[2000s] (S.Afr. gay) a male homosexual who dresses like a stereotypical lesbian.

SE in slang uses

In compounds

diesel therapy (n.) [the diesel engine of the bus that transports the prisoners; the circuit of prisons around which they are taken]

[2000s] (US prison) the constant movement of an inmate between prisons.

In phrases