Jillian sits next to 5 phonetic neighbors — Gillian, Julianna, and Lillian are the closest matches by sound. Most share Jillian's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"youthful"
"gift of God"
"cheerful, glad"
"jasmine flower"
"God's gift"
"burnt meadow"
"jazz music combined with lake or pool"
"gentle horse"
"graceful movement"
"God is gracious"
"strength, virtue"
"wished-for child, beloved"
"oak tree, oak grove"
"God is gracious"
"life"
"white, blessed + peace"
"desired, longed for"
"wished-for child"
"rose of Sharon (biblical flower)"
Similar sound: These names share phonetic patterns with Jillian — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Jillian.
Rhythm: Jillian is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.