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"Concreto" is an adjective which is often translated as "concrete", and "hormigón" is a noun which is also often translated as "concrete". Learn more about the difference between "concreto" and "hormigón" below.
concreto(
kohn
-
kreh
-
toh
)An adjective is a word that describes a noun (e.g., the big dog).
1. (real)
a. concrete 
El líder del proyecto quiere ideas concretas que podamos llevar a cabo inmediatamente.The project leader wants concrete ideas that we can put into effect immediately.
a. concrete 
David es una persona que piensa más en lo concreto que en lo abstracto.David is someone who thinks more about concrete things than abstract ones.
3. (precise)
a. concrete 
No me han dado una respuesta concreta en cuanto a la beca que solicité.I haven't been given a concrete answer about the scholarship I applied for.
b. specific 
Ahora apliquemos esta teoría en un caso concreto.Let's apply that theory to a specific case.
c. particular 
Tengo un interés concreto en la ley internacional.I have a particular interest in international law.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
4. (material) (Latin America)
Regionalism used in Latin America: all the countries in South America, Central America, and the Caribbean. Does not include Spain.
el hormigón(
ohr
-
mee
-
gohn
)A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
1. (material)
a. concrete 
Las paredes son de hormigón y no podemos perforarlas.The walls are made of concrete and we can't drill through them.