The Collaborative International Dictionary of English v.0.48:

Losenger \Los"en*ger\, n. [OF. losengier, losengeor, fr.
   losengier to deceive, flatter, losenge, flattery, Pr.
   lauzenga, fr. L. laus praise. Cf. Lozenge.]
   A flatterer; a deceiver; a cozener. [Obs.] --Chaucer.
   [1913 Webster]

         To a fair pair of gallows, there to end their lives
         with shame, as a number of such other losengers had
         done.                                    --Holinshed.
   [1913 Webster]