1. Arse, arsehole – n., variants of ass and asshole. Can also be used to mean bothered ("Can't be arsed") or acting the fool ("Stop arsing about!"). Mild.

2. Bastard – n., illegitimate child or mongrel; objectionable fellow, probably one who has won one over on you; unpleasant situation ("I'm having a bastard of a morning!"). See also: git, rotter, swine.

3. Bell, bellend – n., head of a penis; fool. (Only write as "bell end" if referring to the end of an actual bell.) Medium strength. See also: dickhead, knobend.

4. Berk – n., idiot. Very mild, yet apparently originated as rhyming slang for "Berkeley hunt".

5. Bint – n., derogatory synonym for woman appropriated from the Arabic word for daughter or girl. Avoid, on the whole.

6. Blimey, blimey O'Reilly, cor blimey, gorblimey – n., expression of astonishment. Thought to derive from the phrase "God blind me!" Terribly mild. See also: crikey.

7. Blighter – n., person or thing to be regarded with contempt/envy. See also cad, rotter, swine. Mild.

8. Bloody – adv., intensifier, popularly used in the phrase "Bloody hell!" Very common, medium strength.

9. Blooming – adj., basically a very mild, somewhat archaic form of "bloody". Use with abandon.

10. Bollocks – n., testicles. Used to mean rubbish or nonsense, as in the exclamation of disbelief "Bollocks!" and the album title Never Mind the Bollocks, Here's the Sex Pistols; in phrases such as "the dog's bollocks" to mean something definitive and perfect; and, in the related word bollocking, a dressing-down ("I gave the useless fool a bollocking"). Medium strength, and very common.