red-sear
/ˌrɛdˈsɪə/Founding
noun
A defect of iron in which it becomes brittle when red-hot, typically due to an excess of sulphur in the metal; = red-shortness. Now rare.
Origin
Late 17th century; earliest use found in Randle Holme (1627–1700), herald painter. Probably originally from red-sear. In later use probably an alteration of either red-short, red-short, or redshire, after sear.