In biology, eukaryote is the term given to all one-celled and multi-celled organisms that have cells with an enclosed nucleus. The word is Greek in origin. Eu means “true” and karyon means “kernel,” and refers to the nucleus. All manner of one-celled beasties, plants, fungi, birds, bats, dinosaurs, and dingoes, and people, are eukaryotes. It is truly the most diverse and inclusive group we all belong to. No judgment. Welcome to the club.