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"Cebollas" is a form of "cebolla", a noun which is often translated as "onion". "Mollera" is a noun which is often translated as "head". Learn more about the difference between "mollera" and "cebollas" below.
la mollera()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
1. (colloquial) (anatomy)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).
a. head
Usa casco al andar en bici para protegerte la mollera.Wear a helmet when you ride your bike to protect your head.
2. (colloquial) (mind)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).
a. head
¿Por qué es tan difícil que te entre en la mollera que no quiero volver a verte?Why is it so hard for you to get it into your head that I don't want to see you anymore?
a. soft spot
La mollera de los bebés es muy frágil y debe tratarse con extremo cuidado.Babies' soft spots are extremely fragile and should be handled with utmost care.
b. fontanelle (technical)
A word or phrase that is only used by experts, professionals, or academics in a particular field (e.g., exposition).
La mollera delantera permanece abierta hasta que el bebé tiene más de dos años.The front fontanelle remains open well into a baby’s second year.
la cebolla()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
1. (vegetable)
a. onion
El cocinero siempre pone cebolla picada en sus tacos.The cook always puts chopped onion in his tacos.