1.
If you say that someone had some hard luck , or that a situation was hard luck on them, you mean that something bad happened to them and you are implying that it was not their fault. ( INFORMAL )
We had a bit of hard luck this season...
= bad luck
N-UNCOUNT
2.
If someone says that a bad situation affecting you is just your hard luck , they do not care about it or think you should be helped, often because they think it is your fault. ( INFORMAL )
The shop assistants didn’t really want to discuss the matter, saying it was just my hard luck.
= tough luck
N-UNCOUNT : poss N
3.
You can say ‘ hard luck ’ to someone to show that you are sorry they have not got or done something that they had wanted to get or do. ( INFORMAL )
Hard luck, chaps, but don’t despair too much.
= tough luck
CONVENTION [ feelings ]