Idiosyncrasy
From Tarisms
Idiosyncrasy is defined as a structural or behavioral characteristic peculiar to an individual or group. The term can also be applied to symbols. Idiosyncratic symbols mean one thing for a particular person, as a blade could mean war, but to someone else, it could symbolize a knighting. By the same principle, linguists state that words are not only arbitrary, but also largely idiosyncratic signs.