Pronunciation: (un'dur-lī"ing),[key] —adj. 1. lying or situated beneath, as a substratum.
2. fundamental; basic: the underlying cause of their discontent. 3. implicit; discoverable only by close scrutiny or analysis: an underlying seriousness in his witticisms. 4. (of a claim, mortgage, etc.) taking precedence; anterior; prior.
5. Ling.belonging to an earlier stage in the transformational derivation of a sentence or other structure; belonging to the deep structure.