"At bay" is a commonly used phrase that refers to keeping something or someone at a safe distance or under control. Other synonyms for this phrase include "under control", "contained", "restrained", "held back", "moderated" and "suppressed". You may also use other words such as "curbed", "restricted", "warded off", "fended off", "kept in check" or "held in abeyance" as alternatives to "at bay". These synonyms are helpful when describing a situation where one has managed to prevent something from getting out of hand or bringing it to a halt. They are particularly useful in written communication and can help add some variety to your vocabulary.