 Traditionally, however, a distinction has been made by linguists between "sex" and "gender", where "sex" refers primarily to the attributes of real-world entities – the relevant extralinguistic attributes being, for instance, male, female, non-personal, and indeterminate sex – and grammatical gender refers to a category, such as masculine, feminine, and neuter (often based on sex, but not exclusively so in all languages), that determines the agreement between nouns of different genders and associated words, such as articles and adjectives.