nevvy

"nevvy" is a regional or dialect word meaning a grandson. It is most likely picked up from family, a particular part of the country, or a piece of regional media. There is nothing to worry about: dialect vocabulary is a sign of place and heritage, not of any risky behaviour. If anything, it is a nice opportunity to talk about where the word comes from and which side of the family or which place uses it.

"nevvy" is regional / dialectal English meaning a grandson. It is mainly heard in British English (and Irish English). A more formal or neutral equivalent would be something like "a grandson" expressed in standard vocabulary. A common mistake is to use "nevvy" outside its region; speakers from elsewhere may not understand it or may find it self-consciously local. If you are a B2 or C1 learner, it is useful to recognise this word when you hear or read it, but think carefully about whether the situation really calls for it before using it yourself.