The antonyms for the phrase "laying open" can be varied depending on the context it is used in. For example, synonyms for "laying open" could include closing, covering, concealing, hiding, or burying. In the case of exposing something, antonyms could include shielding, guarding, protecting, veiling, or obscuring. Further, antonyms could also depend on the object that is being exposed. For instance, if the object is a wound, the antonyms could be healing, sealing, or covering. If the object is a document, the antonyms could be sealing, encrypting, or filing away. The appropriate antonyms for "laying open" will change based on the specific circumstance it is being used in.