A plant of the genus Lithospermum, known for its extremely hard seeds and formerly used in herbal medicine.
From Old English gromwell or similar Germanic roots; possibly related to words meaning 'coarse' or 'rough,' describing the seed texture. Also called 'stone seed' because the seeds are so hard.
Gromwell seeds are so hard that medieval people thought they could cure kidney stones—the idea being that taking something equally hard might 'crack' the problem. It didn't work, but it shows how creative people got with medicine before chemistry.
Complete word intelligence in one call. Free tier — 50 lookups/day.