In many Spanish-speaking countries the word compañero is used frequently to refer to one someone of an equal status, such as a coworker or classmate. It is often translated in English as comrade.
The noun compañero is like most Spanish nouns with a human referent. The masculine forms are used when the referent is known to be male, a group of males, a group of mixed or unknown gender, or an individual of unknown or unspecified gender. The feminine forms are used if the referent is known to be female or a group of females.