the world > food and drink > food > fruit and vegetables > [adjective] > tough-skinned
the world > life > the body > skin > textures or states of skin > [adjective] > tough
1746 (new ed.) xxii. 304 The Province Olives are..more leather like skin'd, yet better for the stomach then the Spanish.
1896 B. M. Croker 18 An active, leather-skinned man.