What does "sclerotic" mean?

Additional senses

1. 2.(Med.) Affected with sclerosis; sclerosed. Sclerotic parenchyma (Bot.), sclerenchyma. By some writers a distinction is made, sclerotic parenchyma being applied to tissue composed of cells with the walls hardened but not thickened, and sclerenchyma to tissue composed of cells with the walls both hardened and thickened.
2. 3.The sclerotic coat of the eye. See Illust. of Eye (d).
3. 4.Pertaining to, or designating, an acid obtained from ergot or the sclerotium of a fungus growing on rye.