"Religiously" [adverb]

Does this word have two separate meanings? I am just wondering, because the common English definition notes that it means "regularly" or "consistently". These definitions may imply some sort of strict, consistent regulation or rule as it would be in conservative religions. Just recently, my Psych instructor used the term in a sentence in her lecture, "She [the professor] doesn't hold onto the concept so religiously. Other professors believe that there is no single part of the brain that controls ___," which then makes me conclude that she is using the term to mean "stubbornly". That, or she is misusing the term. I believe that the underlying assumption is that religious dogma is unchanging, consistent, and always true. Am I right? I once corresponded with a liberal Christian who retorted that "dogma" meant something that was widespread, not something that couldn't change. In any case, I think the whole example is a case where language can subtly influence beliefs about the world.