meaning - What does it mean to have a 'saucy facial expression'?

It depends if you are in Britain or America.

In the great Puritan United States it means simply 'expressing a bold, spirited, or lively manner'.

In Britain it can have a number of meanings, the most likely being 'sexually suggestive in a light-hearted and humorous way'. But it can also mean simply 'cheeky and impertinent' and have nothing to do with sex at all. It depends on context.

If a barmaid, when taking your order for turkey says 'are you a breast man, or a leg man', that is a 'saucy remark' in the first sense. People also talk about 'saucy postcards' which you buy at the seaside, featuring cartoons of red-faced men and overweight or underweight, scantily clad women, with double-entendre captions. They also are 'saucy' in the sexual sense.

If someone writes you a sarcastic letter of complaint, let's say about some business dealings, which you consider unreasonable, you might refer to it as a 'saucy letter'. That is the second meaning.

Remember that in Britain we pronounce the word 'SORSEY'. Americans say something that sounds like 'SASSY'.

• Meanings taken from Oxford Dictionary of English (not OED)