Prior to 1955, gender in modern English only referred to grammatical gender.

In 1926, Henry Watson Fowler stated that the definition of the word pertains to this grammar-related meaning:

“Gender…is a grammatical term only. To talk of persons…of the masculine or feminine g[ender], meaning of the male or female sex, is either a jocularity (permissible or not according to context) or a blunder.”