Gr. skleros: hard] • A type of sclerenchyma cell, commonly found in nutshells, that is not elongated.

a cell that has a thick, typically lignified secondary wall and that typically lacks a protoplast when mature; the "stone cell" of a pear (Source: Dickison, 2000, p.513)

A relatively short sclerenchyma cell, often irregular in shape. See also sclerenchyma.