Carrera

The word carrera looks like career but usually it means your area of undergraduate study.

• ¿Qué carrera estás estudiando? What's your major? ¿Contabilidad? ¿Administración de empresas? ¿Ingeniería civil?
• ¿Qué carrera vas a escoger? What will you major in? What are you going to study in university?
• Acabar tu carrera. Finish college/university. After you receive your degree, you are a licenciado/a.
• Unas chavas de la prepa o de la carrera. Some friends from high school or friends who I studied with in college.

Note that your college major qualifies you for honorary membership in that profession for life. If your undergraduate major was mathematics, you will always be considered a matemático. This is true even if you don't have a doctorate or if you work in something unrelated.

Trayectoria

When talking about career histories, don't overlook trayectoria. This word is especially common when talking about the careers of performers. Su trayectoria artística comenzó a los diez años. She started acting when she was ten. (press interview)

Race

Carrera, of course, is also race. Here are some examples and related expressions:

• Carrera de cien metros. 100 meter dash.
• No me carrerees, eh. Don't rush me.
• Hacer algo a la carrera. Do something in a rushed, hurried way.