- 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.
- a mountain range in Pennsylvania, Maryland, West Virginia, and Virginia: a part of the Appalachian Mountains.
Also called Al·le·ghe·nies.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for allegheny
Her new book, Allegheny County, The Story of America's Crumbling Infrastructure will be published by FSG in 2013.Participants in the 2011 Women in the World Summit
The Daily Beast
March 1, 2011
In 1867 he was appointed director of the Allegheny Observatory at Pittsburgh.The Age of Invention
He suggested the Indian trail across the Allegheny Mountains.Watch Yourself Go By
Al. G. Field
These were called the Alligewi, from which we have derived the name Allegheny.Stories of New Jersey
Frank Richard Stockton
The Allegheny Mountains also held the settlers back for a long time.Conservation Reader
Harold W. Fairbanks
The vegetation on this ridge appears superior to that of the Allegheny.Travels in North America, From Modern Writers
- a mountain range in Pennsylvania, Maryland, Virginia, and West Virginia: part of the Appalachian system; rising from 600 m (2000 ft) to over 1440 m (4800 ft)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.