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

Jim's stock market commentary , market analysis , stock pick breakdowns , and Club Members' Mailbag offer an MBA-caliber finance education that is easy to absorb and apply to your personal investing strategies. —CNBC, 13 Feb. 2026

Advertisement The premise is enough of a murder-show Mad Lib to suggest, correctly, that a creator of this caliber won’t be taking it at face value. —Judy Berman, Time, 13 Feb. 2026

Kyle Pitts is the top option, but there aren’t a ton of starting-caliber tight ends on the market, which could drive up his price tag. —Chad Graff, New York Times, 11 Feb. 2026

The Cowboys will likely acquire a starting-caliber outside corner this offseason. —Joseph Hoyt, Dallas Morning News, 11 Feb. 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