To push or poke through.
is a push through.
Typically a push through is responded by White, and a cut by Black follows. See push cut.
If White tenuki for some reason and Black plays on a subsequent turn, the move is called a tsukinuki ツキヌキ (penetrate through). White is in bad split shape.
When degiri above is too severe, White may allow tsukinuki by defending one side ( is yurumeru in Japanese). Marked white stones are probably sacrificed.