The Collaborative International Dictionary of English v.0.48:

Overslaugh \O"ver*slaugh`\, n. [D. overslag.]
   A bar in a river; as, the overslaugh in the Hudson River.
   [Local, U. S.] --Bartlett.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Overslaugh \O`ver*slaugh"\, v. t. [D. overslaan.]
   To hinder or stop, as by an overslaugh or an impediment; as,
   to overslaugh a bill in a legislative body; to overslaugh a
   military officer, that is, to hinder his promotion or
   employment. [Local Cant, U. S.]
   [1913 Webster]