In a while is a common phrase that means "after some time has passed." However, there are a variety of synonyms for this phrase that can add variety and richness to your language. For example, you might use the phrase "after a bit" or "after a spell" to convey a similar sense of time passing. Other popular synonyms for in a while include "later on," "down the road," and "eventually." Ultimately, the choice of synonym will depend on the specific context and tone of your writing or speech, but incorporating these options can help to keep your language fresh and engaging.