The phrase "be gilded" refers to something that is covered in gold, giving it a luxurious and expensive appearance. The antonyms for "be gilded" would be words such as "be plain," "be ordinary," "be drab," or "be dull." These words denote a lack of ornamentation and are used to describe things that are unadorned or lacking in decoration. While being plain or dull may seem unappealing, it can also be charming in its simplicity, and it can also be more practical and functional than something that is gilded and purely decorative. Overall, the antonyms of "be gilded" offer an alternative approach to design and style.