John Rupert,1890–1960, English linguist.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a relatively narrow inlet of the sea, esp in Scotland
Word Origin for firth
C15: from Old Norse fjörthr fiord
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
"arm of the sea, estuary of a river," early 15c., Scottish, from Old Norse fjörðr (see fjord).
Online Etymology Dictionary, © 2010 Douglas Harper
A long, narrow inlet of the sea. Firths are usually the lower part of an estuary, but are sometimes fjords.
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