"What is religion? Is your commitment to animal rights and veganism a religion, ravi? Is there a reason why it's important to continue using religion in a derogatory way -- to diss people's belief systems -- while (on the surface) appearing to defend it? Or is it just an attempt to charge people with hypocrisy?"
Defenders of religiosity have claimed that any passionate interest anyone has, no matter what about, is that person's religion. ("You say I'm religious? Well science is YOUR religion!" / "Socialism is his religion.") But "religion" doesn't simply mean "passionate conviction" nor does it just mean "belief system."
As far as I'm aware, "religion" indicates a belief in God(s) or the supernatural, including a whole host of crap like angels, demons, an afterlife, virgin births, resurrections from the dead, water turning to wine, Hell, final judgment, avatars and reincarnations, etc., etc. with moral lessons haphazardly strung throughout fantastic tales, as in Aesop's fables. The major monotheist religons generally tout this stuff but claim most items of note happened thousands of years ago in the Middle East, through revealed holy books or texts. This is the sort of thing that characterizes a religion, afaik -- supernatural beliefs, faith, revealed texts.
There's also the slang sense of "religion," as in "Skateboarding is his RELIGION," which means a devotion to something to an almost irrationally fervent degree.
-B.