bullpen

noun

bull·​pen ˈbu̇l-ˌpen 

also ˈbəl-

variants or less commonly bull pen

plural bullpens also bull pens

1

: a large cell where prisoners are detained until brought into court

Commonly called the "bullpen," the court lockup is behind the courtroom and is used as a holding area for prisoners …

—Bruce A. Scruton

2

a

: a place on a baseball field where pitchers warm up before they start pitching

In the bullpen, Goose Gossage is warming up.

—Tony Scherman

b

: the relief pitchers of a baseball team

After five innings Seattle led 14-2 and, with baseball's best bullpen waiting to protect the lead should starter Aaron Sele falter …

—Sports Illustrated

3

: an open work area not divided into offices

… an alternative to the traditional combination of private offices for the brass and bullpens for the workers.

—Carl Ruff

Examples of bullpen in a Sentence

Recent Examples on the Web

Sasaki threw a full bullpen and is in line to start another Cactus League game this week. —Bill Plunkett, Oc Register, 16 Mar. 2026

But credit goes to Texas State's bullpen. —Caleb Yum, Austin American Statesman, 15 Mar. 2026

Who is filling out this bullpen? —Justice Delos Santos, Mercury News, 15 Mar. 2026

Oh, and of course Yamamoto was warming in the bullpen when Freddie Freeman hit his walk-off home run to end the 18-inning Game 3 epic at Dodger Stadium. —Los Angeles Times, 15 Mar. 2026

The bullpen has allowed just two runs (one earned run) on six hits and nine walks with 21 strikeouts over 22 2/3 innings. —Jordan McPherson, Miami Herald, 14 Mar. 2026

While there remains uncertainty about the bullpen and the bench, and whether Jose Caballero can adequately command shortstop for the long haul, one area where there should be no concerns for the Yankees this year is starting pitching. —Bill Madden, New York Daily News, 14 Mar. 2026

Though the Red Sox have veteran lefty Aroldis Chapman in the closer role, this version of Weissert could be a significant boon for the bullpen, should manager Alex Cora find himself in need of a righty closer. —Gabrielle Starr, Boston Herald, 14 Mar. 2026

Working on it in the pitching lab or during bullpens can provide only so much feedback without seeing how hitters handle it. —Meghan Montemurro, Chicago Tribune, 14 Mar. 2026

Word History

First Known Use

1809, in the meaning defined at sense 1

Rhymes for bullpen

• again
• airmen
• amen
• culmen
• flagmen
• gunmen
• lawmen
• oilmen
• playpen
• schoolmen
• tegmen
• ben

Kids Definition

bull pen

noun

1

: a large cell where prisoners are held until brought into court

2

a

: a place on a baseball field where relief pitchers warm up

b

: the relief pitchers of a team