A fellow member of a team can be referred to as a MATE, COMRADE, or TEAMMATE. The term 'MATE' is a four letter word that is commonly used in British English to refer to a friend or companion. The term 'COMRADE' is a seven letter word that is often used to refer to a close friend or ally, especially in a political context. The term 'TEAMMATE' is an eight letter word that is used to refer to a member of the same team or group. All three terms are used to refer to someone who is part of the same team or group.