The Hebrew root 'mn' is the basis for words like, "true", "sure", "faithful", "steadfast". For instance, when we say "amen" after a prayer, it's from that Hebrew root and we really say "truly". Ammon is a name in the Book of Mormon as well as in the Bible. The meaning is a bit unclear. It could be linked to this same root, but because there are two 'm's, there is some uncertainty. But in any case, we seem to be dealing with a Hebrew wordplay in Alma 18:10. This is where king Lamoni expresses admiration for Ammon.
he was more astonished, because of the faithfulness [mn] of Ammon, saying: Surely [mn] there has not been any servant among all my servants that has been so faithful [mn] as this man [whose name is Ammon(=faithful?)]
I think that's pretty cool
