Non-u

I may also note here that the U-demarcation is of two types: – (1) a certain U-feature has a different, non-U counterpart as non-U wealthy / U rich; (2) a certain feature is confined to U-speech and it has a counterpart which is not confined to non-U speech e.g. the pronunciations of girl as [ɡɛl], (? [ɡjɛl]), [ɡæl], [ɡɛəl] are U, but many (perhaps most male) U-speakers, like all non-U-speakers, use the pronunciation [ɡəːl].

Source: wiktionary

Pudding when used to mean all sweet dishes at the end of a meal is Non-U; the U expression is sweet. Similarly greens for vegetables is a Non-U expression.

Source: wiktionary

A wedding is a great occasion for u/non-u indicators. The u mother will be quietly dressed; the non-u one will be more ostentatious and have a corsage. The u father will be wearing his own morning coat and a carnation. The non-u father will bolster his carnation—on his hired morning coat—with a sprig of fern, and perhaps even carry a pair of grey gloves.

Source: wiktionary

The U/non-U priority rule will be in accord with servant master-type rules if masters are U and servants are non-U, for then the rules support each other. But since a master who cannot command is not a master, a non-U sergeant must take priority over a U-recruit, the same with impoverished aristocratic chauffeurs working for nouveau-riche plebeian millionaires.

Source: wiktionary