I believe the village was named this more as a joke or tourist oddity than anything else, but it does have a meaning. It roughly translates as 'Saint Mary's Church in the hollow of the white hazel near a rapid whirlpool and the Church of St. Tysilio of the red cave'.

I'll attempt to tell you how to pronounce it, but unless you're familiar with our Welsh language it will only be approximate. Thlan-vyre-pooth-gwin-guth-gogairich weern-drob-ooth thlan-tusilio-gog-o-goch. Phew! The "ch"s, by the way, are pronounced as in the Scottish word loch, or as in J. S. Bach.