Lekker is a broad use term... yeah 'nice' is lekker.
Lekker can be used to describe food that tastes good/great.
It can be used to describe a day or a place. A Lekker area, lekker weather, some people use it in all sorts of ways in slang.
It is an Afrikaans word.
Here is Ricus Nel with Lekker Ou Jan. Jan is a guy's name.