machicolation

n. opening in a projecting parapet or in the floor of a gallery or roof through which missiles could be dropped on attackers

A machicolation is a floor opening between the supporting corbels of a battlement, through which stones and lethally hot liquids could be dropped on attackers at the base of a defensive wall. The design was developed in the Middle Ages when the Norman crusaders returned (see Normans). A machicolated battlement projects outwards from the supporting wall in order to facilitate this. A hoarding is a similar structure made of wood, usually temporarily constructed in the event of a siege. One advantage of the machicolation over wooden hoarding is protection behind stone battlements, as well as being fire proof.
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Noun
1. a projecting parapet supported by corbels on a medieval castle; has openings through which stones or boiling water could be dropped on an enemy
(hypernym) parapet, breastwork
(derivation) machicolate

(n.)
The act of discharging missiles or pouring burning or melted substances upon assailants through such apertures.
  

(n.)
An opening between the corbels which support a projecting parapet, or in the floor of a gallery or the roof of a portal, shooting or dropping missiles upen assailants attacking the base of the walls. Also, the construction of such defenses, in general, when of this character. See Illusts. of Battlement and Castle.
  

machicolation /,mætʃikou'leiʃn/ (machicoulis) /,mɑ:ʃi'ku:li/
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