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"Viruela" is a noun which is often translated as "smallpox", and "sarampión" is a noun which is often translated as "measles". Learn more about the difference between "viruela" and "sarampión" below.
la viruela()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
el sarampión()
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
