(1):

(v. i.) To lie below or under.

(2):

(n.) See Underlay, n., 1.

(3):

(v. t.) To be subject or amenable to.

(4):

(v. t.) To be at the basis of; to form the foundation of; to support; as, a doctrine underlying a theory.

(5):

(v. t.) To lie under; to rest beneath; to be situated under; as, a stratum of clay underlies the surface gravel.