The Collaborative International Dictionary of English v.0.48:

Headborough \Head"bor*ough\ Headborrow
\Head"bor*row\(h[e^]d"b[u^]r*[-o]), n.
   1. The chief of a frankpledge, tithing, or decennary,
      consisting of ten families; -- called also borsholder,
      boroughhead, boroughholder, and sometimes
      tithingman. See Borsholder. [Eng.] --Blackstone.
      [1913 Webster]

   2. (Modern Law) A petty constable. [Eng.]
      [1913 Webster]