If you ever studied Spanish, you may have learned that Spanish words come in two genders, masculine and feminine. That's wrong. There are six:
Masculine — el niño.
Feminine — la niña.
Neutral — very few exist in Spanish, but a big one is lo, an all-purpose pronoun.
Epicene — words in which the gender does not indicate the sex. These are almost always names of animals, like la cabra, "the goat." To indicate a male goat, you have to say la cabra macho, "the male goat."
Common — words like pianista or "pianist," which do not vary. For male and female pianists, you refer to el pianista or la pianista.
Ambiguous or vacillating — words like mar or "sea," which can be el mar or la mar and the meaning is the same.
— Sue Burke