In Spanish, the word for stamps is sellos. Stamps are commonly used for mailing letters and packages, and the term sellos is widely recognized in Spanish-speaking countries.
For example, if you want to ask for stamps at a post office in a Spanish-speaking country, you could say: “¿Dónde puedo comprar sellos?” which translates to “Where can I buy stamps?”
Understanding this term can be very useful, especially if you are traveling or sending mail internationally.