A "panther" in dating is a slang term that refers to a woman who likes older men. It is the opposite of a "cougar," which is a term used to describe an older woman who is interested in younger men. The term "panther" is not widely used and may not be familiar to everyone. It is possible that the term has different meanings in different contexts, but in the dating context, it generally refers to a woman who is attracted to older men.