The word "aestuous" is a rare and quite lovely adjective that means "passionate" or "full of heat." It's not a word you'll hear every day, but when you do come across it, you'll be able to use it to describe a particularly ardent emotion or feeling. The spelling of "aestuous" is pronounced "es-chew-us," with the "ch" making a hard "k" sound. It's a fun word to say and a great way to impress your friends with your extensive vocabulary!