Jr sits next to 3 phonetic neighbors — Jay-Are, Junior, and Jerome are the closest matches by sound. Most share Jr's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"junior, the younger one"
"ruler of the spear"
"sacred songs, hymns of praise"
"modern coined name"
"God is salvation"
"elder, presider"
"sky, heaven"
"king, ruler"
"strict, disciplined"
"firm, steadfast"
"pledge, hostage"
"to be, to exist, present"
"house guardian"
"God is gracious (John) + ruler of the home (Henry)"
"thankful, he will judge"
"companion of God"
"of the river (if -von is from Welsh afon)"
"shepherd, sheep herder"
"heart, mind"
"skilled, expert, proficient"
"olive tree man"
Similar sound: These names share phonetic patterns with Jr — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Jr.
Rhythm: Jr is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.