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"Condimentar" is a transitive verb which is often translated as "to season", and "sazonar" is a transitive verb which is also often translated as "to season". Learn more about the difference between "condimentar" and "sazonar" below.
condimentar(
kohn
-
dee
-
mehn
-
tahr
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
1. (culinary)
a. to season 
Alice condimentó el pollo con limón y ajo.Alice seasoned the chicken with lemon and garlic.
sazonar(
sah
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soh
-
nahr
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
3. (to make sweet) (Caribbean)
Regionalism used in the Caribbean: Cuba, the Dominican Republic, and Puerto Rico
a. to sweeten 
Sazoné el té con dos cucharaditas de miel.I sweetened the tea with two teaspoons of honey.
sazonarse
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
a. to mature 
El estilo del compositor se sazonó durante su estadía en París.The composer's style matured during his stay in Paris.