What is the opposite gender to him?

Opposite genders are those who determine sex. Those are masculine, feminine, common and neuter.

Masculine determines male sex, such as ambassador and salesman.

Feminine determines female sex, such as ambassadress and saleslady.

Common determines either a male or a female sex, such as cat and human.

And the last gender, Neuter does determine inanimate things. This means it IS neither a male or a female. Examples are ball, keyboard and headband.

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