Zen sits next to 4 phonetic neighbors — Ben, Ken, and Ten are the closest matches by sound. Most share Zen's Japanese cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"meditation, absorption"
"God knows"
"ever high, the highest"
"coined celebrity name"
"God heals"
"plow blade maker or user"
"messenger, herald"
"great one"
"roof maker"
"scholar"
"love, passion transformed"
"little cloak, beloved"
"genuine, authentic, honest"
"eternal, perpetual"
"boisterous, spirited, lively"
"ruler of the people"
"God sees, God is my strength"
"tile maker, one who tiles"
"perceiving sounds, hearing the world's cries"
"land bordering the sea"
"case, container (via Old French)"
Similar sound: These names share phonetic patterns with Zen — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Sanskrit via Japanese origins, giving them the same cultural heritage as Zen.
Rhythm: Zen is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.