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Definition of castlereagh

castlereagh

/ˈkæs.əl.reɪ/
Cas · tle · reagh

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castlereagh Lexical Profile

• noun

1

British A prominent Anglo-Irish politician and statesman (1769–1822), formally Robert Stewart, Viscount Castlereagh, who served as British Foreign Secretary and was instrumental in orchestrating the European settlement at the Congress of Vienna.

Example

"Historians often debate whether Castlereagh was a pragmatic diplomat who secured European peace or a reactionary oppressor of reform."


2

Irish A geographical area and former local government district in Northern Ireland, situated to the south and east of Belfast.

Example

"The family traced its ancestry back to a small farming community in the borough of Castlereagh."


3

Australian An inland river in New South Wales, Australia, which forms part of the Macquarie catchment within the Murray-Darling basin.

Word Origin & Etymology

Derived from the Irish 'an Caisleán Riabhach', meaning 'the grey castle'. It originated as a place name in County Down, Northern Ireland, and later gained international prominence as the noble title of the British statesman Robert Stewart, Viscount Castlereagh.

Usage Trend

Historical frequency of usage in published text.

180019102020

Cite this Entry


Wordmom. (2026). Definition of Castlereagh. In Wordmom Dictionary. Retrieved Oct 17, 2026, from https://wordmom.com/dictionary/castlereagh
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