stiffener

Short definition from Wiktionary

Noun

1. 1
   Anything added to something in order to stiffen it, such as a support beam, or starch for a collar.
2. 2
   One of a series of angle bars, Z-bars, beams, rods, or other shapes, attached in order to provide them the necessary stiffness or rigidity.
3. 3
   An alcoholic drink taken to fortify oneself.