Definitions
1.verbTo lay (something) underneath something else; to put under.
2.verbTo provide a support for something; to raise or support by something laid under."to underlay a cut, plate, or the like, for printing"
3.verbTo put a tap on (a shoe).
4.verb(of a vein, fault, or lode) To incline from the vertical.
5.verbTo lie in a position directly beneath.
6.verbTo lie under or beneath."A stratum of clay underlies the surface gravel."
7.verbTo serve as a basis of; form the foundation of."a doctrine underlying a theory"
8.verbTo be subject to; be liable to answer, as a charge or challenge.
9.verbTo underlay.