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"Femenina" is a form of "femenino", an adjective which is often translated as "female". "Pez" is a noun which is often translated as "fish". Learn more about the difference between "pez" and "femenina" below.
el pez()
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
2. (material)
femenino, el femenino()
An adjective is a word that describes a noun (e.g., the big dog).
2. (womanlike)
a. feminine
Marcos tiene un cuerpo delgado y un rostro muy femenino.Marcos has a thin body and a very feminine face.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).