The Collaborative International Dictionary
Interfacial
Interfacial \In`ter*fa"cial\, a. (Geom.)
Included between two plane surfaces or faces; as, an interfacial angle.
Of or pertaining to an interface.
Wiktionary
interfacial
a. Of or pertaining to an interface
WordNet
interfacial
adj. relating to or situated at an interface; "an interfacial layer"; "interfacial tension is the surface tension at the interface between two liquids"
Usage examples of "interfacial".
Such explosions are known to affect the interfacial membrane that you call the Path.