Interpretation semantics for this word are undefined.

( -- x₁ x₂ ) ( R: x₁ x₂ -- x₁ x₂ )

Copy cell pair x₁ x₂ from the return stack. Semantically equivalent to R> R> 2DUP >R >R SWAP.

3.2.3.3 Return stack, 6.1.0580 >R, 6.1.2060 R>, 6.1.2070 R@, 6.2.0340 2>R, 6.2.0410 2R>.