It’s just a catchy marketing name for prior, similar game that was called “Yacht,” supposedly because the creators played it on their yacht.
“Yahtzee” was trademarked in 1956 by Edwin Lowe. He was a salesman who had previously renamed another game “Bingo” and marketed it successfully.
Lowe’s company was bought by Milton Bradley in 1973, which was subsequently acquired by Hasbro in 1984.