The Collaborative International Dictionary of English v.0.48:

Situate \Sit"u*ate\ (?; 135), Situated \Sit"u*a`ted\, a. [LL.
   situatus, from situare to place, fr. L. situs situation,
   site. See Site.]
   1. Having a site, situation, or location; being in a relative
      position; permanently fixed; placed; located; as, a town
      situated, or situate, on a hill or on the seashore.
      [1913 Webster]

   2. Placed; residing.
      [1913 Webster]

            Pleasure situate in hill and dale.    --Milton.
      [1913 Webster]

   Note: Situate is now less used than situated, but both are
         well authorized.
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Situate \Sit"u*ate\, v. t.
   To place. [R.] --Landor.
   [1913 Webster]

WordNet (r) 3.0 (2006):

situate
    v 1: determine or indicate the place, site, or limits of, as if
         by an instrument or by a survey; "Our sense of sight
         enables us to locate objects in space"; "Locate the
         boundaries of the property" [syn: situate, locate]
    2: put (something somewhere) firmly; "She posited her hand on
       his shoulder"; "deposit the suitcase on the bench"; "fix your
       eyes on this spot" [syn: situate, fix, posit,
       deposit]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "situate":
   allocate, assign, collocate, deploy, dispose, emplace, fix,
   get a fix, home in on, install, localize, locate, navigate,
   pin down, pinpoint, place, position, put, put in place, set, spot,
   triangulate, zero in on