The Casual Vacancy employs a number of British terms within the context of the story:
- Casual vacancy - a situation in politics in which a seat in a deliberative assembly is vacated during that assembly's term
- City - a population centre which has been granted a Royal charter (traditionally, one which has at least one Anglican cathedral, but this is no longer the criterion). Contrast with the American English usage, wherein a city is any population centre above a certain size.
- Comprehensive - a type of state school found in Great Britain and certain other countries that does not select its intake on the basis of academic achievement or aptitude
- Fag - a cigarette
- GCSE - General Certificate of Secondary Education, an educational certification in Great Britain
- Loo - the bathroom or toilet. (In British English "bathroom" is specifically a room with a bath, though in homes the toilet is usually in there as well)
- Mock - a preliminary exam to prepare one for a real exam
- Nappy - diaper
- Nursery school (sometimes just nursery) - British term for what is called "preschool" or "kindergarten" in American English
- People carrier - a large (typically 7-seater) car, to carry an entire family.
- Prick - slang term for penis or an inconsiderate person
- Squash - a high-speed racket sport developed in England
- Twat - someone who is stuck up or proper
- Wog (or rarely golliwog or golly) - a coloured person, especially one of darker skin tone. Despite being the basis of Florence Kate Upton's heroic Golliwogg character, is now an offensively racist term, due in large part to Enid Blyton's interpretation of the archetype.
- Yob or yobbo - an antisocial person, especially a particularly young or violent one