/sub"teuh rayn', sub'teuh rayn"/ , n.
a cave or subterranean room.
Also, subterrain, subterrene /sub"teuh reen', sub'teuh reen"/ .
[ 1605-15, in sense "subterranean"; 1765-75 for current sense; subterraneus subterranean, equiv. to sub- SUB- + terr ( a ) earth + -aneus composite adj. suffix, equiv. to -an ( us ) -AN + -eus -EOUS ]