The Collaborative International Dictionary of English v.0.48:
Sublease \Sub"lease`\, n. (Law) A lease by a tenant or lessee to another person; an underlease. --Bouvier. [1913 Webster]WordNet (r) 3.0 (2006):
sublease n 1: a lease from one lessee to another [syn: sublease, sublet] v 1: lease or rent all or part of (a leased or rented property) to another person; "We sublet our apartment over the summer" [syn: sublet, sublease]