Allegheny

American  

[al-i-gey-nee] / ˌæl ɪˈgeɪ ni /

noun

1. a river flowing NW from Pennsylvania into SW New York and then S through W Pennsylvania, joining the Monongahela at Pittsburgh to form the Ohio River. 325 miles (525 km) long.

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Other Word Forms

• Alleghanian adjective
• Alleghenian adjective
• trans-Alleghenian adjective

Example Sentences

“We built it for USAir,” Allegheny County executive Rich Fitzgerald said many years later, “hoping that they would grow jobs here, putting their hub and their headquarters here.”

From Slate • Nov. 24, 2025

North Hills Community Outreach, which runs three food pantries in Pennsylvania’s Allegheny County, saw an almost 50% increase in the number of people lining up for food last week.

From The Wall Street Journal • Nov. 11, 2025

Where I’m from, everybody who is Black in our city has a reference point to the Allegheny County Jail, which is in the middle of Pittsburgh.

From Los Angeles Times • Apr. 17, 2025

Allegheny County officials told the BBC that the group had come to apply for mail-in ballots and the officials reiterated that only US citizens can register to vote.

From BBC • Oct. 30, 2024

A month later, the Allegheny County coroner’s jury convened in Pittsburgh to examine the evidence.

From "Fannie Never Flinched" by Mary Cronk Farrell