The Collaborative International Dictionary of English v.0.48:

Sublet \Sub*let"\, v. t. [imp. & p. p. Sublet; p. pr. & vb. n.
   Subletting.]
   To underlet; to lease, as when a lessee leases to another
   person.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sublet
    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]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "sublet":
   charter, chartered, employed, farm, farm out, hire, hire out,
   hired, hireling, job, lease, lease out, lease-back, lease-lend,
   leased, lend-lease, let, let off, let out, mercenary, paid, rent,
   rent out, rented, sublease, subleased, underlease, underlet