The phrase "keep within compass" means to stay within the boundaries or limits of something. There are several synonyms for this phrase that can be used to convey the same meaning. For example, the term "stay within bounds" can be used to describe someone who is adhering to rules or regulations. Similarly, "keep it in check" suggests that someone is monitoring their behavior and actions to ensure they don't go beyond what is allowable. Others synonyms for "keep within compass" include "limit yourself," "restrain yourself," "stay within limitations," and "stay on track." All of these phrases are useful for expressing the concept of staying within the confines of something.