How to remove the word on top of articles photos

Hello there,

on my store, I have some products on sale. You know, every product has an image. On top of the images of products on sale, there is the word “on sale”. I want to remove or change that word. Is that possible with no additional plugin and without checking the WordPress file?

Thank you in advance.

• This topic was modified 11 minutes ago by govisola.

The page I need help with: [log in to see the link]