Vana's list "Number Names" of 20 great name ideas: Quartus  - Quintinu !

Number Names

Quartus 

Shiro 

Tetra 

Penta

Pompea 

Pompeia 

Five 

Quentijn 

The feminine Quinta is virtually unused in the US, though male forms of the Roman family name Quintus, such as Quintin and Quentin, are quite popular. That may change with the emergence of comedian and actress Quinta Brunson, creator of the television show Abbott Elementary.

In the Netherlands, the short form Quinty is widely used, and in the US, the related Quincy is becoming popular for girls. Quinn, an unrelated Irish surname-name with a similar feel, is in the girls' Top 100 in the US. Ancient roots coupled with modern rarity make Quinta a highly desirable name.
 
A modern bearer is Quinta Brunson — creator of the sitcom Abbott Elementary.

Quinta

Quintavia 

Quintella 

Quintí

Quintilian 

Quintilianus 

Quintilis 

Quintillus

The daintiest and most accessible of the many Q names for a fifth child, now used for girls situated anywhere in the birth order. 

Quintina

Quintine 

Quintino is a masculine name of Latin origin, derived from 'Quintus,' which literally means 'fifth' in Latin. Historically, Roman families would often name their fifth-born child Quintus, though it later became used regardless of birth order. The -ino suffix adds an Italian diminutive quality, giving the name a warm, affectionate tone. The name is most common in Italian, Portuguese, and Spanish-speaking regions. Quintino has historical significance in various countries, including being the name of Portuguese republican revolutionary Quintino Bocaiúva. The name combines classical Roman heritage with a melodic Southern European quality, appealing to parents seeking a name with historical depth that remains relatively uncommon in English-speaking countries.

Quintino

Quintinu 