Allegheny

American

[al-i-gey-nee] / ˌæl ɪˈgeɪ ni /

noun

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.

Other Word Forms

Alleghanian adjective
Alleghenian adjective
trans-Alleghenian adjective

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The Pirates have been a perpetual laughingstock ever since Barry Bonds ditched the Allegheny for the San Francisco Bay after leading Pittsburgh to the National League Championship Series in 1992.

From The Wall Street Journal • Apr. 9, 2026

In Pennsylvania, Democrat Jen Mazzocco won her race in Allegheny County by 64 points — doubling the margin her predecessor had posted in 2024.

From Salon • Feb. 25, 2026

“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

He eventually was carted off and taken to Allegheny General Hospital in critical condition.

From Los Angeles Times • Sep. 11, 2025

She said that it was really fun with everyone all dressed up and dancing to good music played by a deejay instead of The Gypsies of the Allegheny.

From "The Perks of Being a Wallflower" by Stephen Chbosky

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023