LAMONI

LAMONI

Lehite PN		King of land of Ishmael, 1st c. BC (Alma 17:21; Alma 24:5)

This name is not immediately suggestive of an etymology. Perhaps something like the root suggested for Laman, but with 1c.s. pronominal suffix or a gentilic ending. 
However, neither ending would cause the vowel to change from a to o.

Reynolds & Sjodahl first connected Lamoni to Laman, though without explaining how the two were related (R&S, 26). The connection was made again, but this time the 
gentilic ī ending was suggested (JAT & RFS), similar to the gentilic “Israelite.” 

Much less likely is an archaic form of the Hebrew for “to me,” “for me,” “mine.” This would also be unlikely as a name (JH).