Tenaille

A tenaille (archaic tenalia) is an advanced defensive-work, in front of the main defences of a fortress, which takes its name from resemblance to the lip of a pair of pincers.

[2] In a letter to John Bradshaw, President of the Council of State in London, Oliver Cromwell writing from Dublin on 16 September 1649 described one such tenaille that played a significant part during the storming of Drogheda.

There was a Tenalia to flanker the south Wall of the Town, between Duleek Gate and the corner Tower before mentioned;—which our men entered, wherein they found some forty or fifty of the Enemy which they put to the sword.

To protect the postern, an outwork, originally V-shaped, was placed in front of the gate, providing an area where the defenders could leave the fortification without being seen or directly shot at.

[4][5] Also shown is another approach to protect a gate; the roughly triangular outwork seen in the middle of the bottom drawing is a ravelin.