As a Noun: 1. The belief in a god or gods and the activities that are connected with this belief, such as prayer, worship in a church or temple. English = religion. 2. A particular system of belief in a god or gods and the activities connected with this system. English = religion. As a Verb or Adjective: 1. To have a strong belief in a god or gods. English = (be) religious. 2. To be connected to or related to religion. English = (be) religious.