B

[ball bag]

Scrotum.

[balls up]  {n.}

A bungled or messed up situation. (WWI Service slang).

[bang to rights]

Caught in the act.

[bang up]  {v.}

1. To lock up in prison (prison slang).

2. To inject an illegal drug.

[barney]  {n.}

a noisy quarrel or fight. Sometimes claimed to be rhyming slang (Barney Rubble, trouble) but actually dates back to 19th century.

[bender]

a drinking binge.

[bent]  {adj.}

1. dishonest or corrupt,

2. homosexual (mildly derogatory).

[bent as a nine bob note]

Extremely dishonest or corrupt. A nine shilling (bob) note never existed and would therefore have to be counterfeit.

[berk]  {n.}

(also spelled burk) idiot, stupid person (from Berkeley Hunt, Cockney rhyming slang for cunt)

[Billy]

1. Amphetamines (from Billy Whizz, a British comic strip character.)

2. Friendless ([Billy No-Mates])