nBaton-sinistera well-known heraldic indication of illegitimacy, improperly called Bar-sinister, a diminutive of a bend-sinister, not extending to the sides of the shield, so as to resemble a marshal's baton laid diagonally over the family arms from left to right
Chambers's Twentieth Century Dictionary
Fr. bâton—Low L. basto, a stick; of unknown origin.
BATON-SINISTER, a bend-sinister like a marshal's baton, an indication of illegitimacy.
"The Nuttall Encyclopaedia" by Edited by Rev. James Wood