Subterrene

Full definition of subterrene

Adjective

1. underground, subterranean
• 1927, H. P. Lovecraft, w, Then he saw a sort of grey phosphorescence about, and guessed they were coming even to that inner world of subterrene horror of which dim legends tell, and which is litten only by the pale death-fire wherewith reeks the ghoulish air and the primal mists of the pits at earth’s core.