Oshi

Oshi is a basic technique in Go, where a player pushes directly against the opponent’s stone, usually on the second, third, or fourth line. This move limits the opponent’s liberties and can control the direction of play. While pushing can build influence and restrict the opponent’s options, excessive or poorly timed pushing may lead to overconcentration or loss of initiative.

Pushes often occur during contact fights and influence-building sequences. 

It’s important to distinguish oshi from hai (crawl). The move is only called oshi if it pushes the opponent’s stones from the side or above. If played directly beneath the opponent’s stone along the second or the third line, it is called hai.