The phrase "spill the beans" is often used to refer to revealing a secret or sharing confidential information. However, there are several antonyms for this phrase that suggest keeping secrets or maintaining discretion. Some of these include "keep mum," "zip one's lips," "hold one's tongue," "clam up," and "stay tight-lipped." These expressions are often used to urge someone to be discreet or to caution them against revealing something that should be kept secret. Whether you choose to spill the beans or keep quiet, it is always important to consider the consequences of sharing sensitive information.