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

• quality

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 lethality of ammunition is much beyond caliber size or muzzle velocity. —Atharva Gosavi, Interesting Engineering, 30 Oct. 2025

This hurricane season came close to shattering records, trailing only 2005 for having the most Category 5 hurricanes in a single season, which saw three storms of that caliber. —Matt Nighswander, NBC news, 30 Oct. 2025

Just kidding - but honestly not sold on him being the best player on a championship caliber team. —The Athletic Nba Staff, New York Times, 30 Oct. 2025

Nothing has opened in Cincinnati of the same caliber since, according to Rashdan and his team. —Bebe Hodges, Cincinnati Enquirer, 28 Oct. 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