תְּֽהִי־יָ֭דְךָ עַל־אִ֣ישׁ יְמִינֶ֑ךָ עַל־בֶּן־אָ֝דָ֗ם אִמַּ֥צְתָּ לָּֽךְ׃
願你的手護佑你右手所扶持的人，護佑你為自己所堅固的那人。
Radak
ואביו קרא לו בנימין, meaning “the son of my right hand.” The name suggested that the child is especially beloved seeing that he was born when his father was already advanced in years. We find the word ימין used in the sense of being especially beloved in Psalms 80,18 וכן תהי ידך על איש ימינך, “grant Your help to the man at Your right hand, etc.” The end of the verse על בן אדם אמצת לך, “the one You have adopted as Your own,” spells out this meaning beyond any doubt.