The Collaborative International Dictionary of English v.0.48:

Latitat \Lat"i*tat\, n. [L., he lies hid.] (O. Eng. Law)
   A writ based upon the presumption that the person summoned
   was hiding. --Blackstone.
   [1913 Webster]

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

LATITAT, Eng. law. He lies hid. The name of a writ calling a defendant to
answer to a personal action in the king's bench; it derives its name from a
supposition that the defendant lurks and lies hid, and cannot be found in
the county of Middlesex, (in which the said court is holden,) to be taken
there, but is gone into some other county, and therefore requiring the
sheriff to apprehend him in such other county. Fitz. N. B. 78.