a way of holding someone's arm from behind with one of your arms and holding their neck with the same hand, so that it is difficult for them to move, used in wrestling (= a sport in which two people fight and try to throw each other to the ground)

I had one of his arms in a half nelson behind his back. 我用一招半扼颈，把他的一条手臂扭到背后。

a bad situation that is difficult to escape from

We need to reform these outdated laws that have the economy in a half-nelson. 我们要改革这些遏制经济发展的过时法律。