Yes, gloss is a Scrabble word!

Verb

1. Give a shine or gloss to, usually by rubbing

2. Provide interlinear explanations for words or phrases

3. Provide an interlinear translation of a word or phrase

4. Give a deceptive explanation or excuse for

Noun

1. An explanation or definition of an obscure word in a text

2. An alphabetical list of technical terms in some specialized field of knowledge; usually published as an appendix to a text on that field

3. The property of being smooth and shiny

4. An outward or token appearance or form that is deliberately misleading