verb trans (usu in passive)
to wrench open or tear apart or to pieces
to wrench (something) open or tear it apart
archaic to split (wood or stone) with force or violence
They unpacked their basket under an aged walnut with a riven trunk out of which bumblebees darted — Edith Wharton
to rend (a country, etc) with distress or dispute
archaic said of wood or stone: to become split
[Middle English riven from Old Norse rīfa]