isamiashi means a situation in which an attacking rikishi accidentally steps too far forward and out of the ring, his opponent thus winning. Lexicurio rates it Rare gem — a strength score of 82 out of 100.
Etymology
Borrowed from Japanese 勇み足, literally "forward step out".
noun
- a situation in which an attacking rikishi accidentally steps too far forward and out of the ring, his opponent thus winning