OE grot sand, gravel ＜ Gmc reutam (G Griess) ← IE ghru- to rub (Gk khrs🔗⭐🔉

OE grot sand, gravel ＜ Gmc reutam (G Griess) ← IE ghru- to rub (Gk khrs skin, 《原義》 rough surface): cf. great, grits grith /gr/

研究社新英和大辞典 ページ 193816 での【G Griess】単語。