The Collaborative International Dictionary of English v.0.48:

Girt \Girt\, v. t. [imp. & p. p. Girted; p. pr. & vb. n.
   Girting.] [From Girt, n., cf. Girth, v.]
   To gird; to encircle; to invest by means of a girdle; to
   measure the girth of; as, to girt a tree.
   [1913 Webster]

         We here create thee the first duke of Suffolk,
         And girt thee with the sword.            --Shak.
   [1913 Webster]