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"Pupitre" is a noun which is often translated as "desk", and "escritorio" is a noun which is also often translated as "desk". Learn more about the difference between "pupitre" and "escritorio" below.
el pupitre(
poo
-
pee
-
treh
)A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
1. (furniture)
a. desk 
Todas las respuestas del examen estaban escritas en mi pupitre.All of the answers to the exam were written on my desk.
¡Jonah! ¡Qué asco! ¡No pegues tu chicle debajo del pupitre!Jonah! Gross! Don't stick your gum under the desk!
el escritorio(
ehs
-
kree
-
toh
-
ryoh
)A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
1. (furniture)
a. desk 
Es más fácil hacer la tarea en un escritorio que la mesa de la cocina.It is easier to do homework at a desk than at the kitchen table.
b. bureau  (United Kingdom)
Regionalism used in the United Kingdom
El escritorio de la reina Isabel está hecho de roble.Queen Elizabeth's bureau is made of oak.
2. (office)
a. office 
Mi abogado tiene un escritorio en el centro de la ciudad.My lawyer has an office downtown.
3. (computer)
a. desktop 
Haz clic en el ícono de la aplicación en el escritorio.Click on the application icon on the desktop.