The word 女友 is formed by directly combining two independent concepts: 女 (nǚ), meaning "female" or "woman", and 友 (yǒu), meaning "friend". By placing these characters side-by-side, a new, composite idea is created where the meaning of the first element, "female", specifies and modifies the category of the second, "friend", resulting in the specific concept of a "female friend", which conventionally refers to a romantic girlfriend. It is a straightforward, logical construction of meaning through semantic combination.