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

• class
• grade
• 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

The law prohibits the sale, manufacture, possession and purchase of assault-style weapons, assault weapon attachments and .50 caliber cartridges in the state of Illinois. —John Bacon, USA TODAY, 25 Feb. 2025

The new movement, caliber 7138, does something few other perpetual calendars do – and which Audemars Piguet has never done before. —Carol Besler, Forbes, 25 Feb. 2025

Not long ago, parting ways with this Hall of Fame caliber player was inconceivable. —Reader Commentary, Baltimore Sun, 24 Feb. 2025

Robert Morris owns the Smith & Wesson M&P .40 caliber gun, police said. —Emily Shapiro, ABC News, 24 Feb. 2025

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