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"Una" is a noun which is often translated as "one", and "los" is a definite article which is often translated as "the". Learn more about the difference between "una" and "los" below.
la una()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
1. (time)
los()
A definite article is a word that identifies a noun as specific or known to the speaker (e.g., the girl).
A pronoun is a word that stands in for a noun (e.g., she).
