BILL  Here's a typical definition of religion:  re·li·gion rəˈlijən/ noun noun: religion
  the belief in and worship of a superhuman controlling power, especially a personal God or gods.  ideas about the relationship between science and religion 
      synonyms:	faith, belief, worship, creed; More
    sect, church, cult, denomination
    "the freedom to practice their own religion"
        a particular system of faith and worship.
        plural noun: religions
        "the world's great religions"
        a pursuit or interest to which someone ascribes supreme importance.

Note especially that first sentence "the belief in and worship of a superhuman controlling power, especially a personal God or gods."  You might stretch this to claim that antheism, the categorical denial of a god, is, somehow, a religion.  I would grant it is a "belief", but not a religion.  I'm just a simple old agnostic...there may or may not be a god, I haven't a clue.  regards, Gary Crum