ឡូយណាស់

Yes! It is gender-neutral. It means she has a cool style or attitude.

It's not 'rude' per se, but it's too informal. It's like calling your professor 'dude.' Better to use 'L'or nas.'

'Sa'at' means beautiful/pretty. 'Loy' means cool/stylish. A traditional dress is 'Sa'at,' but a leather jacket is 'Loy.'

You say 'Min loy te' (មិនឡូយទេ).

Only if the presentation is very artistic and modern. For taste, always use 'Chnganh.'

No, it's been around since at least the 1960s, though its popularity fluctuates.

Sometimes 'acting loy' (tveu loy) can mean someone is being arrogant or showing off.

It's a superlative version. 'Os steah' means 'to the limit' or 'breathless.'

It's better to use 'Sa'at' for nature. 'Loy' is usually for human-made things or actions.

Almost never. You won't see it in newspapers unless they are quoting someone or writing about youth culture.

It's a smooth glide, like the 'y' in 'boy.'

The formal equivalent would be 'Sangkha' (for men) or 'Toan somay' (modern/trendy).

Some do, especially those who were young in the 60s, but it's primarily a youth word.

Yes, 'Loy!' on its own works as an exclamation like 'Cool!'