So, if [name]Octavia[/name] means the eighth born child, what would babies number one through seven be named? Are there even names meaning first, second third, etc. born?
[name]Septimus[/name] is for the seventh born, that’s the only one I know.
Sort of. If you look at [name]Neil[/name] Gaiman’s ‘Stardust’ the princes and princess are named for the order in which they’re born.
[name]Una[/name], [name]Primus[/name], Secundus, [name]Tertius[/name], Quartus, [name]Quintus[/name], [name]Sextus[/name], [name]Septimus[/name], [name]Octavius[/name], Novus, [name]Decimus[/name] etc
20000-NAMES.COM: Naming Tips & Quips: Numbering One's Children < This has some more information,
I love Stardust! I’ve also come across the female forms; Quintella, [name]Septima[/name] & [name]Decima[/name]. There are probably lots of different versions in different languages. I know that Kensa, [name]Nessa[/name] & [name]Tressa[/name] mean first, second and third in Cornish 
Yay! [name]Neil[/name] Gaiman replied to me on Twitter once. It’s still probably one of the greatest moments of my life, lol.
[name]Neil[/name] Gaiman rocks! I’ve met him a few times, he’s such a sweetie, very personal, it makes sense that he’s the type who replies to Liverpool girls on twitter 
And he’s married to [name]Amanda[/name] of The [name]Dresden[/name] Dolls, how awesome is that???
I like the Latin numbers too, and the Cornish ones are sweet too.
[name]Amanda[/name] [name]Palmer[/name]!
I love all the five names: [name]Quentin[/name], [name]Quincy[/name]…
I know a boy who was a fourth called Quaddy and a third called [name]Trey[/name]. Three could also be [name]Trip[/name] or [name]Tripp[/name].
That’s her full name, yes! Thanks 
So awesome. My six degrees of separation is shrinking! Lol.
I love [name]Neil[/name] Gaiman!
Back on topic:
I was gathering numeral names in an attempt at writing a Sci-Fi novel which I abandoned and wrote my fantasy novel instead so I have some extensive lists. All these names have some meaning like “__ born”
Boys:
1 – Akia, [name]Alpha[/name], Baako, Chaska, Hiapo, [name]Jada[/name], [name]Kazuo[/name], Mosi, Okpara, Primeiro, Shinichi, So, Taro, Uno, Wynono
2 – Eiji, [name]Kenji[/name], Lado, [name]Manu[/name], [name]Pili[/name], Secondo, Zinan
3 – Mensa, Saburo, Taizo, Terciero
4 – Anan, Anang, Cuartio, Fodjour, Quarto, Shiro
5 – Anum, Buinton, Cinco, Enu, [name]Quentin[/name]
6 – Essien, Msrah, Nsia, [name]Sextus[/name]
7 – Ashon, Asong, [name]Bay[/name], Nsoah, Nsonowa
8 – Awotwe, Botwe, Hachiro, Oktawian, [name]Octavius[/name], [name]Tam[/name]
9 – Akron, Akrong, Nkruma, [name]Nonnie[/name], Nono, [name]Tisa[/name]
10 – Badu, [name]Decimus[/name], Ond
11 – Dubaku
12 – Adeben
13 – Adusa, [name]Odissan[/name]
14 – Agyeman
15 – Odinan
Girls:
1 – Abiba, [name]Alpha[/name], Baako, [name]Dede[/name], Hatsu, Hatsuko, Hiapo, Kapuki, Mosi, [name]Prima[/name], Teyacapan, [name]Una[/name], [name]Winona[/name]
2 – Kekona, Poni, Segunda, Tlacotl, [name]Ulu[/name]
3 – Kunto, Mansa, Terceira
4 – Anan, Manang, [name]Pita[/name], [name]Quartilla[/name], Rabah, [name]Rabia[/name]
5 – Enu, Penthea, Quincylla, [name]Quintana[/name], Quintella, Quinyette
6 – Nsia
7 – Asong, Nsonowa
8 – Awotwi, Botwe, [name]Octavia[/name]
9 – Ennea, Nkruma, [name]Tisa[/name]
10 – Badu, Baduwa
11 – Dubaku
Then there’s just using a number ([name]Seven[/name] seems to be popular right now)
I love stardust and [name]Neil[/name] Gaiman too! But I actually replied to say that my middle name is [name]Quinn[/name] and I was given that name because I was the fifth child. None of my siblings have names to go along with their birth order though!
you could go with with what people like the Novogratz family did and just name your kid Five (or [name]One[/name] or Two) 
A few comments–
For 2, you could use [name]Gemini[/name], [name]Thomas[/name], Cowen, or something meaning twin.
For 3, it’s common in the southern US for [name]Billy[/name] [name]Bob[/name] III to be called [name]Tre[/name]/[name]Trey[/name].
[name]Roman[/name] family have the -gens or family name and then add the number to it-- so [name]Julia[/name] Maior and [name]Julia[/name] [name]Minor[/name] (elder and younger) or [name]Julia[/name] [name]Tertia[/name] (third). Some Korean families I know do this where the names they call each within the family are “older sister” or “youngest” or “middle.”
[name]Sheva[/name] means 7 in Hebrew and girls are commonly named “[name]BatSheva[/name], [name]EliSheva[/name]…”
I can list some more number names when I find my [name]Oxford[/name] Latin Dictionary but I learned last year in class that in most [name]Roman[/name] families the boys would get individual names and girls would be named after their father. A man named Iulius (no J’s in Latin) would have [name]Iulia[/name] [name]Prima[/name], [name]Iulia[/name] Secunda, [name]Iulia[/name] [name]Tertia[/name], etc.
0: Zira* ([name]Lion[/name] [name]King[/name] character) , [name]Noel[/name]/[name]Nolan[/name] (sounds like “null/noll” which means zero), [name]Nadia[/name],
1/4: [name]Courtney[/name] (if you say “korter” for quarter)
1/2: [name]Demi[/name]
1: [name]Prima[/name], [name]Una[/name]/[name]Oona[/name], [name]Unity[/name], [name]Primus[/name]
2: Secundus([name]Roman[/name]), [name]Segundo[/name], anything with a “two” sound (such as [name]Tulio[/name]), [name]Di[/name]ane/[name]Diana[/name] (Prefix)
3: [name]Tertia[/name]/[name]Tertius/name, [name]Tristan[/name], [name]Tricia[/name], anything with a tri-, [name]Trey[/name], [name]Tripp[/name], [name]Trinity[/name]
4:Quartus([name]Roman[/name])
5: [name]Quintus/name, [name]Quinn[/name], [name]Quentin[/name]/[name]Quinton[/name]), [name]Quinlan[/name]*, Fievel(sounds like five) [name]Quinn[/name]- anything
6: [name]Sextus/name, Six itself(name of tv character), [name]Seth[/name]?(sounds like prefix)
7: [name]Septimus[/name]/[name]Septima/name, [name]Seven[/name]
8: [name]Octavia[/name]/[name]Octavian[/name]/[name]Octavius[/name], [name]Otto[/name](8 in Italian), [name]Kate/name, [name]Creighton[/name](contains eight)
9: Nonus([name]Roman[/name]), [name]Nona[/name], [name]Nina[/name], [name]Ninian[/name], [name]Nova[/name], Ennea
10: [name]Decima[/name]/[name]Decimus[/name], [name]Tenley[/name], [name]Declan[/name] (deca-)
11: [name]Lev[/name], [name]Levin[/name]
100: [name]Hector[/name](Hecto- prefix)
1000: [name]Killian[/name], [name]Keely[/name]/[name]Keelin[/name] (kilo), [name]Millie[/name], [name]Millicent[/name]
1,000,000: [name]Megan/name, [name]Maximilian[/name]
1 billion: [name]Nan[/name], [name]Nancy[/name] (nano-)
1 trillion: [name]Tera[/name], [name]Tara[/name], [name]Taran/name
1 quadrillion(10^15): [name]Peta[/name], [name]Petra[/name], [name]Peter[/name] (peta-)
1 quintillion(10^18): [name]Alexa[/name] (exa-)
1 sextillion(10^21): [name]Zetta[/name]