Predeceased is a term used to describe someone who died before another person. However, there are several other words and phrases that can be used as synonyms for predeceased. These include words like passed away, expired, deceased, departed, and no longer with us. Furthermore, other terms that might work include phrases such as "gone before us," "departed this life," and "no longer living," among others. These synonyms can be used interchangeably with predeceased in conversation, writing, or any other context where a person is looking for an alternative word to use.