An invasion of an opponent's territory that makes the opponent's territory dead or a bihk (seki).
Bob Myers: It seems odd that there would be a term used for an invasion which sometimes results in your opponent dying, sometimes in his living. What is the etymology of this word?
Sazn: Not sometimes. is the Hubimsu.
unkx80: I think the implication is that what looks like solidified territory is actually not, as proved by the Hubimsu of .
By the way, the correct play for both players is shown below, with the usual convention that seki is better than ko for the defender.
liopic: Hubimsu comes from Hubim + su(move). Hubim is the participle of the verb hubida (후비다) which means "pick the nose", "pick the ear".
Sazn: The First Example was a seki too
unkx80: But can open an approach ko.
Sazn: I believe this is better than the approach ko
Alex Weldon: Sure, but if W plays at a, this reverts to the first seki diagram. If B wants to force ko, he must play as above and make it an approach ko.
Bill: The ko threat situation makes a difference. The standard response usually depends on Black's having a big advantage in the ko fight. Most of the time it looks like the next diagram is correct (orthodox play) when Black plays first.
Now each player threatens to play at a. This is better for Black than a seki, but not by much. That's why it's normally better for White to respond at and take sente, rather than to respond at and take gote.
Question: If the play becomes a ko for life and death, is the invasion still Hubimsu?