Girl name · Tupi-Guarani
Jaci
“moon”
Vibes
Common nicknames
Short-forms and diminutives parents often use for Jaci.
Explore Jaci further
Similar-feel alternatives, or middle-name candidates that pair well with Jaci — both ranked by the same scoring system (vibe overlap, syllable rhythm, origin compatibility).
About the name
Jaci is the moon in Tupi-Guarani, and in Tupi cosmology a deity — the mother of plants, paired with Guaraci the sun. It is pronounced roughly zha-SEE in Brazilian Portuguese, which is not what the spelling suggests to English readers.
It is used in Brazil as part of the indigenous-name revival that also brought back Iara, Potira and Ubirajara. It has no US ranking, and English speakers will consistently say JAY-see unless corrected.
The pronunciation gap is the main thing to weigh. Two syllables want two (Jaci Amara, Jaci Luna). On our vibe map it is Boho with a Celestial core.
Jaci — common questions
Is Jaci a boy or girl name?
Jaci is traditionally a girl name of Tupi-Guarani origin.
What does the name Jaci mean?
Jaci means “moon” of Tupi-Guarani origin. Jaci is the moon in Tupi-Guarani, and in Tupi cosmology a deity — the mother of plants, paired with Guaraci the sun. It is pronounced roughly zha-SEE in Brazilian Portuguese, which is not what the spelling suggests to English readers.
Where does the name Jaci come from?
Jaci is Tupi-Guarani in origin. It is used in Brazil as part of the indigenous-name revival that also brought back Iara, Potira and Ubirajara. It has no US ranking, and English speakers will consistently say JAY-see unless corrected.
What are common nicknames for Jaci?
Jac and Cici — the short-forms parents most often use for Jaci.
How popular is Jaci?
Jaci did not make the top 1,000 girls' names in US Social Security Administration data for 2025, which makes it genuinely rare in the US.
Bring the name into the room
A couple of nice things named Jaci you might want for the nursery.