the.com/characteristic

means A quality or feature typical of a person or thing, one that helps mark it as distinct from others.

from From Greek 'kharaktēr,' originally meaning a tool for engraving or the mark stamped by it — like a die pressed into coin or wax, leaving an impression that identifies the source. The Greeks extended this to mean a distinguishing mark of someone's nature, and that sense traveled through Latin into French and English. So the word still carries its old literal job: a 'characteristic' is the stamp that shows whose impression you are.