Sivan sits next to 4 phonetic neighbors — Sienna, Ivan, and Siobhan are the closest matches by sound. Most share Sivan's Hebrew-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"third Hebrew month (May-June)"
"happy, fortunate (related to Asher)"
"natural spring, oasis"
"God is gracious"
"dew of heaven, my dew"
"light"
"grace; God has favored me"
"song of God"
"grace, favor"
"helped by God, God has helped"
"azure, referring to the Azores islands"
"grace, favor"
"Baal is the prince (Phoenician interpretation)"
"small, little"
"my father rejoices, father's joy"
"wonderful"
"my father is Yahweh"
"swift one (by association with a bird in flight)"
"the descender (referring to the Jordan River)"
Similar sound: These names share phonetic patterns with Sivan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew/Akkadian origins, giving them the same cultural heritage as Sivan.
Rhythm: Sivan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.