Becoming a member of an organization or group is a common way to gain access to exclusive benefits and privileges. Joining, enrolling, and entering are all terms used to describe the process of becoming a member. Joining is a four letter word that means to become part of a group or organization. Enrolling is a five letter word that means to register as a member of a group or organization. Entering is also a five letter word that means to JOIN or take part in something. All three words can be used to describe the process of becoming a member.