Noah Boy
NOH-uh
“rest, comfort” · Hebrew
#2
Caius
BoyLatin· “form of Gaius, perhaps 'rejoice'”
- Meaning
- form of Gaius, perhaps 'rejoice' (origin disputed)
- Origin
- Latin
- Pronunciation
- KY-uhs
- Syllables
- 1
- US rank 2025
- #927
- US babies 2025
- 254
- Best rank
- #927 (2025)
- Peak year
- 2025
Meaning and origin of Caius
Caius is often said to mean “form of Gaius, perhaps 'rejoice'”; the origin is uncertain, though it is usually linked to Latin roots.
Caius is an old spelling of Gaius, one of the most common Roman first names. Its meaning is uncertain; it is often linked to the Latin gaudere, to rejoice, though scholars have not settled the question. The name was borne by many notable Romans, including Gaius Julius Caesar, and it appears in Shakespeare as Doctor Caius in The Merry Wives of Windsor. At Cambridge University, Gonville and Caius College takes part of its name from the physician John Caius. In English it is usually pronounced KY-us or KAY-us.
Famous parents who chose Caius: Stephen Curry and Ayesha Curry (2024). More celebrity baby names
Popularity over time
Caius first appears in US Social Security records in 1994. It has ranked in the top 1,000 in 1 different years, starting in 2025. It is at its all-time high right now: 2025 brought both its best national rank, #927, and its highest count, 254 babies. Use has grown 84% in ten years.
Its national rank moved from #6,382 in 2000, #2,520 in 2010, and #927 in 2025. Of the 2,329 US boys named Caius since records began, 46% were born in the 2010s, its biggest decade. The 2020s come next, with 1,044 babies.
Other boys' names that peaked around the same time include Shimon, Agastya, Shmuel, Eitan, and Rowdy.
Where it is most popular (2025)
In 2025, Caius ranked highest in Maryland, Minnesota, and Indiana.
| State | Rank there | Babies |
|---|---|---|
| Maryland | #578 | 8 |
| Minnesota | #594 | 8 |
| Indiana | #627 | 10 |
| Tennessee | #642 | 11 |
| Massachusetts | #708 | 6 |
Gender, sound and spelling
In the US it is used almost only for boys.
Caius is usually pronounced KY-uhs, with one syllable. It has five letters, starts with C and ends in “-us”.
Middle names for Caius
A few middle names that flow with Caius: each avoids a matching first letter, a rhyme and a vowel clash where the names meet.
Sibling names for Caius
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Lists that include Caius
Frequently asked questions
What does the name Caius mean?
Caius is often said to mean “form of Gaius, perhaps 'rejoice'”; the origin is uncertain, though it is usually linked to Latin roots.
What is the origin of the name Caius?
Caius has Latin roots. Caius is an old spelling of Gaius, one of the most common Roman first names.
Is Caius a popular name?
Yes. Caius ranked #927 in the US in 2025, which makes it in the top 1,000.
Is Caius a boy or girl name?
Caius is mainly a boy's name. In the US it is used almost only for boys.
How do you pronounce Caius?
Caius 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