The Reidemeister move of type II.
Poke Move
See also
Knot Move, Reidemeister MovesExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Poke Move." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/PokeMove.html