Gloss: (verb): to provide a gloss for : explain, define

“By the end of the semester, you will have learned at least 15 words of your own choosing plus others your classmates have glossed for you (scroll down to the 4th instance of the word, definitions 1a and b).” (Blogging Project guidelines)

This means that by the end of the semester, everyone will have done 15 words, so we each benefit from the definitions and explanations our classmates provide on the site.