The Collaborative International Dictionary of English v.0.48:

Terrar \Ter"rar\, n. [LL. terrarius liber. See Terrier a
   collection of acknowledgments.] (O. Eng. Law)
   See 2d Terrier, 2.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Terrier \Ter"ri*er\, n.
   1. [F. terrier, chien terrier, from terre the earth, L.
      terra; cf. F. terrier a burrow, LL. terrarium a hillock
      (hence the sense, a mound thrown up in making a burrow, a
      burrow). See Terrace, and cf. Terrier, 2.] (Zool.) One
      of a breed of small dogs, which includes several distinct
      subbreeds, some of which, such as the Skye terrier and
      Yorkshire terrier, have long hair and drooping ears, while
      others, at the English and the black-and-tan terriers,
      have short, close, smooth hair and upright ears.
      [1913 Webster]

   Note: Most kinds of terriers are noted for their courage, the
         acuteness of their sense of smell, their propensity to
         hunt burrowing animals, and their activity in
         destroying rats, etc. See Fox terrier, under Fox.
         [1913 Webster]

   2. [F. terrier, papier terrier, LL. terrarius liber, i.e., a
      book belonging or pertaining to land or landed estates.
      See Terrier, 1, and cf. Terrar.] (Law)
      (a) Formerly, a collection of acknowledgments of the
          vassals or tenants of a lordship, containing the rents
          and services they owed to the lord, and the like.
      (b) In modern usage, a book or roll in which the lands of
          private persons or corporations are described by their
          site, boundaries, number of acres, or the like.
          [Written also terrar.]
          [1913 Webster]