Fig. to conceal one's good ideas or talents. (A biblical theme.) Jane has some good ideas, but she doesn't speak very often. She hides her light under a bushel.Don't hide your light under a bushel. Share your thoughts with other people.
to avoid letting people know that you are good at something, usually because you are shy (often in continuous tenses) I didn't realize you could play the piano - you've been hiding your light under a bushel.