Rex

♂ Boy

Pronounced REKS /rɛks/High

Meaning: From the Latin rex (king), the direct Latin word for a monarch; used as a given name evoking royal authority and regal strengthHigh

In 30 seconds: Rex is the single-syllable Latin word for king, a name of stark, unambiguous authority. From ancient Rome to Hollywood, Rex carries a bold, leonine presence that is simultaneously vintage and perpetually powerful.

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Origin HighLatin

MeaningFrom the Latin rex (king), the direct Latin word for a monarch; used as a given name evoking royal authority and regal strength

U.S. rank (2025)#859 ↘ Falling

2025 U.S. births281 boys (0.02% of U.S. boys)

Peak year1951

Total births (all-time)≈ 60,441

Popularity in the U.S. · SSA data

U.S. births per year (Social Security Administration, 1880–present). Pink marker = peak year.

History & Origin

Rex is the Latin word for 'king', one of the most ancient and universal titles of authority. In Rome, Rex was the title of the earliest Roman kings before the Republic (753–509 BC) abolished the monarchy; the very word was considered so dangerous to republican sensibilities that Julius Caesar's assassination was partly motivated by fears he wished to be called Rex. The word is the root of regal, regalia, royal, and regent.

As a given name, Rex was used in ancient Rome and revived in English-speaking countries in the 19th and 20th centuries. Actor Rex Harrison (1908–1990), famous for My Fair Lady, and musician Rex Orange County represent the name's enduring artistic appeal. Rex is experiencing a quiet revival in the 21st century as parents embrace short, strong Latin names.

Did you know? Tyrannosaurus Rex — the most famous dinosaur in history — literally means tyrant lizard king in Latin and Greek, ensuring that Rex is permanently embedded in popular culture as the ultimate symbol of supreme, ancient power.

Overall data confidence 99%

Oxford Latin Dictionary — rex — king; Latin etymologyU.S. Social Security Administration — popularity data

Variations

Rexx

Nicknames

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Famous Bearers

★Rex Harrison (1908–1990)
British actor who won the Academy Award for Best Actor for his portrayal of Professor Henry Higgins in My Fair Lady.

If you like Rex…

Max— same one-syllable Latin strong-meaning name (greatest)

Dex— shares the crisp x-ending one-syllable masculine punch

Jax— same family of short, snappy x-ending names for boys

Axel— same strong consonant-heavy Scandinavian/Latin-rooted masculine energy

Frequently Asked

What does the name Rex mean?

Rex means king in Latin — direct, unambiguous, and powerful.

How do you pronounce Rex?

It is said REKS, one syllable.

Is Rex a popular name?

Rex has been used steadily in English-speaking countries and is experiencing a modern revival as a short, bold Latin name.

Is Rex related to royal?

Yes — Rex (king), royal, regal, and regent all share the same Latin root.