Source : Webster's Revised Unabridged Dictionary (1913)

Pederero \Ped`e*re"ro\, n. [Sp. pedrero, fr. OSp. pedra, Sp.
   piedra, a stone, L. petra, fr. Gr. ?. So named because it was
   at first charged with stones.] (Mil.)
   A term formerly applied to a short piece of chambered
   ordnance. [Written also {paterero} and {peterero}.]