Noah Boy
NOH-uh
“rest, comfort” · Hebrew
#2
Kaius
BoyLatin· “uncertain; variant of Caius”
- Meaning
- uncertain; variant of Caius (origin disputed)
- Origin
- Latin
- Pronunciation
- KY-uhs
- Syllables
- 1
- US rank 2025
- #1,029
- US babies 2025
- 216
- Best rank
- #1,023 (2020)
- Peak year
- 2025
Meaning and origin of Kaius
Kaius is often said to mean “uncertain; variant of Caius”; the origin is uncertain, though it is usually linked to Latin roots.
Ancient Rome is the source of Kaius, a modern spelling of Caius, itself a form of the Roman name Gaius, whose meaning is uncertain. It is sometimes linked to the Latin gaudere, to rejoice, but this connection is not firmly established. Gaius was one of the most common Roman first names, borne by Gaius Julius Caesar, and Caius appears in Shakespeare. The k spelling gives Kaius a fresh, contemporary look while keeping its classical roots.
Famous parents who chose Kaius: Derek Jeter and Hannah Jeter (2023). More celebrity baby names
Popularity over time
Kaius first appears in US Social Security records in 2005. It has never ranked in the national top 1,000, which keeps it genuinely uncommon. Its best national rank was #1,023 in 2020, and the most babies received it in 2025, when 216 were named Kaius. In 2025, 216 babies were named Kaius, and it ranked #1,029 nationally. That is 96% more than ten years earlier, so it is clearly on the rise.
Its national rank moved from #6,207 in 2010 and #1,029 in 2025. Of the 2,011 US boys named Kaius since records began, 57% were born in the 2020s, its biggest decade. The 2010s come next, with 807 babies.
Other boys' names that peaked around the same time include Cashton, Yaseen, Menachem, Avraham, and Zayan.
Where it is most popular (2025)
In 2025, Kaius ranked highest in Louisiana, Wisconsin, and North Carolina.
| State | Rank there | Babies |
|---|---|---|
| Louisiana | #721 | 6 |
| Wisconsin | #735 | 6 |
| North Carolina | #741 | 12 |
| Missouri | #753 | 7 |
| Georgia | #766 | 12 |
Gender, sound and spelling
In the US it is used almost only for boys.
Kaius is usually pronounced KY-uhs, with one syllable. It has five letters, starts with K and ends in “-us”.
Middle names for Kaius
A few middle names that flow with Kaius: each avoids a matching first letter, a rhyme and a vowel clash where the names meet.
Sibling names for Kaius
Similar names
Gus Boy
GUHS
“short form of Augustus or Gustav” · English
#1,331
Caius Boy
KY-uhs
“form of Gaius, perhaps 'rejoice'” · Latin
#927
Lucius Boy
LOO-shuhs
“light” · Latin
#1,129
Linus Boy
LY-nus
“flax” · Greek
#1,913
Zeus Boy
ZOOS
“sky, bright” · Greek
#1,351
Amadeus Boy
am-uh-DAY-uhs
“love God” · Latin
#1,634
Ignatius Boy
ig-NAY-shus
“from Roman family name Egnatius” · Latin
#1,664
Klaus Boy
KLOWS
“German short form of Nikolaus, victory” · German
#2,245
Maximus Boy
MAK-sih-muhs
“greatest” · Latin
#276
Titus Boy
TY-tuhs
“uncertain; a Roman given name” · Latin
#358
Atticus Boy
AT-ih-kuhs
“of Attica” · Latin
#281
Augustus Boy
aw-GUS-tuhs
“venerable, majestic” · Latin
#407
Lists that include Kaius
Frequently asked questions
What does the name Kaius mean?
Kaius is often said to mean “uncertain; variant of Caius”; the origin is uncertain, though it is usually linked to Latin roots.
What is the origin of the name Kaius?
Kaius has Latin roots. Ancient Rome is the source of Kaius, a modern spelling of Caius, itself a form of the Roman name Gaius, whose meaning is uncertain.
Is Kaius a popular name?
Not especially. Kaius ranked #1,029 in the US in 2025, which puts it outside the top 1,000.
Is Kaius a boy or girl name?
Kaius is mainly a boy's name. In the US it is used almost only for boys.
How do you pronounce Kaius?
Kaius is usually pronounced KY-uhs. Stressed syllables are in capital letters.
Popularity figures come from US Social Security card applications (names given to at least five babies in a year, 1880 to 2025). How we source names and meanings