Jemma sits next to 3 phonetic neighbors — Gemma, Emma, and Jenna are the closest matches by sound. Most share Jemma's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"gem, jewel"
"whole, universal"
"maiden of the coral sea"
"lily flower, pure and beautiful"
"queen"
"of the crooked hill"
"fairy queen, princess"
"protector, she who defends"
"gracious, dear, beloved"
"my God has answered"
"hay clearing, hay field"
"dark one (variant)"
"heavenly flower"
"to ward off, protect"
"sunlight, warmth"
"woman of Judea"
"pure, innocent"
"deep affection, devotion"
"high tower"
"rose"
"modern invented name"
Similar sound: These names share phonetic patterns with Jemma — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Italian origins, giving them the same cultural heritage as Jemma.
Rhythm: Jemma is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.