I can appreciate how a single word can fail to present anything meaningful in terms of feedback.
The polish I speak of is in terms of something that looks like it has had a good amount of attention paid to its parts. The sprites, the animated background, and the fact that the game is quite playable and therefore it functions as a demonstration of someone's capability.
In many ways it is the opposite of a game that has more going on, but lacks overall presentation.
So it's good but it could be a bit deeper, and a bit better of a game. There is quite a lot of polish, but it feels unfinished also. Did the game come out to be what you had expected, or wanted, of it? also, do you plan to work on it further?
edit: I now notice that you are the artist. I think you did a really good job