The Collaborative International Dictionary of English v.0.48:

Curtilage \Cur"ti*lage\ (k?r"t?-l?j), n. [OF. cortillage,
   curtillage, fr. cortil court, courtyard, LL. cortis court.
   See Court.] (Law)
   A yard, courtyard, or piece of ground, included within the
   fence surrounding a dwelling house. --Burrill.
   [1913 Webster]

WordNet (r) 3.0 (2006):

curtilage
    n 1: the enclosed land around a house or other building; "it was
         a small house with almost no yard" [syn: yard, grounds,
         curtilage]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

CURTILAGE, estates. The open space situated within a common
enclosure belonging to a dwelling-house. Vide 2 Roll, Ab. 1, l. 30;
Com. dig. Grant, E 7, E 9; Russ. & Ry. 360; Id. 334, 357; Ry &
Mood. 13; 2 Leach, 913; 2 Bos. & Pull. 508; 2 East, P. C. 494;
Russ. & Ry. 170, 289, 322; 22 Eng. Com. Law R. 330; 1 Ch. Pr. 175;
Shep. Touchs. 94.