caliber

noun

cal·​i·​ber ˈka-lə-bər 

British also kə-ˈlē-

variants or calibre

1

a

: degree of mental capacity or moral quality

teachers of high caliber

b

: degree of excellence or importance

the caliber of instruction

2

a

: the diameter of a bullet or other projectile

b

: the diameter of a bore of a gun usually expressed in hundredths or thousandths of an inch and typically written as a decimal fraction

.32 caliber

3

: the diameter of a round or cylindrical body

especially : the internal diameter of a hollow cylinder

Synonyms of caliber

• quality
• rate

Examples of caliber in a Sentence

I was impressed by the high caliber of the team's work.

musicians of the highest caliber perform at that concert hall

Recent Examples on the Web

Also, much of the city’s entertainment is already inside, from Broadway-caliber shows and over-the-top casinos to sprawling spas, luxury shopping, celebrity-chef restaurants, and massive nightlife venues. —Lauren Dana Ellman, Travel + Leisure, 9 June 2026

Improving the laws and caliber of the people who govern are the goals. —Sun Sentinel Editorial Board, Sun Sentinel, 9 June 2026

When someone of Perkins’ caliber is cast in a recurring role, they won’t be expected to just linger in the background. —Nellie Andreeva, Deadline, 9 June 2026

His baseball coaching record speaks for itself, with decades of success, championship-caliber leadership, and a reputation for building programs that reflect excellence both on and off the field. —Nathan Canilao, Mercury News, 8 June 2026

Word History

Etymology

borrowed from Middle French calibre "internal diameter of a cylindrical object, displacement of a gun," borrowed (by uncertain mediation) from Arabic qālab, qālib "mold for casting metal, shoemaker's last," borrowed from Greek kalapod-, kalápous, kalópous "shoemaker's last," from kâla (plural) "wood, timber" (of uncertain origin) + -a- (perhaps after tetrápous "four-footed") or -o- -o- + poús "foot" — more at foot entry 1

First Known Use

1588, in the meaning defined at sense 2b

Rhymes for caliber

• excalibur

Kids Definition

caliber

noun

cal·​i·​ber

variants or calibre

ˈkal-ə-bər 

1

: degree of excellence or importance

2

: the diameter of a missile (as a bullet)

3

: the inside diameter of a gun barrel

Medical Definition

caliber

noun

cal·​i·​ber

variants or chiefly British calibre

ˈkal-ə-bər, British also kə-ˈlē-

: the diameter of a round or cylindrical body

especially : the internal diameter of a hollow cylinder