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What does Caius mean?

Caius Pronunciation of Caius as a boys' name is pronounced keys. It is of Latin origin, and the meaning of Caius is "happy". Common Roman form of Gaius. This was the name of the infamous Roman emperor called Caligula, a nickname meaning "little boots". This referred to the minature soldier's footwear he wore when he was young. A 16th-century English physician endowed a college at Cambridge University called "Gonville and Caius".


ASSOCIATED WITH happy, roman, emperor (king), little, soldier (warrior), 16th century


VARIANTS Cai, Caio, Kay, Kaye, Keye, Keyes, Keys

(male) Caiius, ..

(female) Cais, ..

Caius Niko (C.N.), ..

How popular is Caius?

Caius is an uncommonly occurring first name for men. Caius is an equivalently unusual last name too for all people. (2000 U.S. CENSUS)

Caius was first listed in 2012 and reached its top rank of #1231 in the U.S. in 2016, and is presently at #1356. (2018 BIRTH STATISTICS)

Top 2000 baby names ranking of Caius name in U.S.

Top 100 baby names ranking of Caius outside U.S.

Which version is better?

Popular variation forms of Caius (#1356 THE PREVIOUS YEAR) ranked in the Top 2000 are Cai, Kay and Kaye. Usage of these forms of Caius was well-received among parents 9 decades ago (AVERAGE #1421) and is now significantly diminished, with the form Kay becoming less fashionable.

Top 2000 baby names ranking of Caius, Cai, Kay, Kaye in U.S.

Top 100 baby names ranking of Caius and related baby names outside U.S.

Similar Names

Caius is pronounced similarly to Cace, Case, Cass, Cayce, Caz and Kass. Other recommended sound-alike names are Arius, Cadmus, Caide, Caile, Caily, Cain, Caine, Caird, Cairn, Cairns, Cairo, Calum, Capps, Cassius, Cetus, Claus, Clitus, Comus, Cris, Cyrus, Dacius, Darius, Fabius, Jairus, Janus, Jarius, Magus, Manus, Marius and Pius. These names tend to be more frequently used than Caius.

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in meaning and etymology.