nī̆grēdo, ĭnis, f. [niger],
blackness, black color (post-class.): capilli corvinā nigredine, Ap. Met. 2, 9, 5: nigredo ollae, Vulg. Nah. 2, 10; Mart. Cap. 2, § 137: atrae noctis, id. 1, § 67.