Perhaps my own misinterpretation. The trigger generally refers to a gun, whereas the hammer falling traditionally refers to an auctioneer's mallet, signifying finality. I have not heard of the term used in the context you speak of, however that is a failing on my part and I acknowledge it.![]()
No need to apologize. Firearms are esoteric things.
One pulls the trigger which makes the hammer (that thing people cock back in Westerns) strike the firing pin which sends the bullet off on its merry way.
If you interpose something between the hammer and the firing pin (a finger, perhaps?) you can prevent the gun from going off even if the trigger has released the hammer.