1. common; ordinary; banal; unimaginative.
2. of or relating to this world or earth as contrasted with heaven; worldly; earthly:
3. of or relating to the world, universe, or earth.
With respect #1, I affirm the words "common" and "ordinary" ... though definitely not banal ... and sadly, too often unimaginative.
But #2 and #3 seem terribly important to me.
The idea that faith is woven into every-day life and every-day life woven into faith ... like having lunch, or taking a nap, going for a walk, having a spat with a loved one, brushing one's teeth, watching TV, wondering what it's all about, and a fine glass of wine.
There was a time in my ministry when I wanted faith to be something more than mundane, and the Christian Publishing World, of course, provides entire libraries on how to be anything but mundane.
The contemporary church has spent a lot of time and money puffing up the gospel, and it's too bad, actually. It's less than accurate, finally addicting people to "experience."
So I vote for mundane ... finding God in all the small places of life, places out-of-the-way ... learning to appreciate the commonplace as an environment in which God is likely to be found, sort of like Bethlehem.