In the game of
go, the term "miai" refers to two
points which accomplish the same result; if deprived of one, the other must be played. The idea can be applied to real life as well - if you are in a room with another person, and there are two equally good meals laid out, there is no need to race to one or the other. It is fine to just wait until the other person chooses one.
In go, often there are stones which are being attacked, but it's not necessary to respond, because there are two ways to escape. It's safe to wait until the opponent destroys one of the escape routes, and then just take the other.
The way to attack something that's defended by miai is to attack something else simultaneously. So you cut off one escape route with a move that also attacks another group. If they move to save the other group, you can cut off their last escape. And if they save the first group, you can continue the attack against the other.
It's a form of the japanese verb "miau", which means to counterbalance, or correspond.
Japanese Go terms