What is "paddywhack"

alt. 1 (context dated derogatory English) An Irishman 2 (context rare English) A severe blow (especially in reference to the folk song ''This Old Man'') 3 A strong elastic ligament or tendon in the midline of the neck of sheep or cattle (generally any quadruped) which relieves the animal of the weight of its head n. 1 (context dated derogatory English) An Irishman 2 (context rare English) A severe blow (especially in reference to the folk song ''This Old Man'') 3 A strong elastic ligament or tendon in the midline of the neck of sheep or cattle (generally any quadruped) which relieves the animal of the weight of its head

Paddywhack (also spelt Paddywack) or Nuchal ligament (Latin: Ligamentum nuchae), is a strong elastic ligament in the midline of the neck of sheep or cattle which relieves the animal of the weight of its head. It is pale yellow in colour. (The yellow colour is the elastin on the ligaments.) The name is derived from the corruption of paxwax (originally faxwax Old English hair + to grow).

The nuchal ligament is unusual in being a ligament with an elastic component, allowing for stretch. Most ligaments are mostly made of highly aligned collagen fibres which do not permit stretching.