noun
ko threat
A move in the game of Go played elsewhere on the board to create a threat, forcing the opponent to respond so that the player can recapture the ko.
劫立てを打ってから、もう一度コウを取り返した。
After playing a ko threat, I recaptured the ko.
この局面では有効な劫立てが少ない。
In this position, there are few effective ko threats.
Compound of 劫 (ko, from the Go term for a repetitive capture) and 立て (tate, from 立てる, meaning 'to set up' or 'to make'). The reading こうだて is a standard kun'yomi compound reading.