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"Una" is a form of "una", a noun which is often translated as "one". "Diez" is a form of "diez", an adjective which is often translated as "ten". Learn more about the difference between "una" and "diez" below.
la una(
oo
-
nah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
1. (time)
diez(
dyehs
)An adjective is a word that describes a noun (e.g., the big dog).
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
2. (number)
a. ten
Ella lleva un diez en su camiseta en honor a su jugadora favorita.She wears a ten on her jersey in honor of her favorite player.
b. tenth (in dates)
Celebraremos mi cumpleaños el diez de enero.We'll celebrate my birthday on the tenth of January.