The Collaborative International Dictionary of English v.0.48:

Quadrat \Quad"rat\, n. [F. quadrat, cadrat. See Quadrate.]
   1. (Print.) A block of type metal lower than the letters, --
      used in spacing and in blank lines. [Abbrev. quad.]
      [1913 Webster]

   2. An old instrument used for taking altitudes; -- called
      also geometrical square, and line of shadows.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

39 Moby Thesaurus words for "quadrat":
   acres, chattels real, demesne, domain, em, em quad, en, en quad,
   five-em space, four-em space, grounds, hair space, honor,
   justification space, justifying space, land, landed property,
   lands, lot, lots, manor, messuage, parcel, patent space, plat,
   plot, praedium, property, quad, real estate, real property, realty,
   slug, space, spaceband, tenements, thick space, thin space, toft