Arm
Arm noun - A part of a body of water that extends beyond the general shoreline.
Usage example: this arm of the Atlantic is surprisingly peaceful, as the stronger ocean currents do not reach this far
Firth is a synonym for arm in estuary topic. In some cases you can use "Firth" instead a noun "Arm", when it comes to topics like narrow body of water.
Firth
Firth noun - A part of a body of water that extends beyond the general shoreline.
Usage example: the Firth of Forth in Scotland
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Synonyms for Firth
Mutual synonyms
Both words in one sentence
- Colin Firth's slow-motion walk to the hockey field in wet white shirt with his jacket over his arm mimics a similar scene he did in the 1995 Pride and Prejudice.
Source: Film / St. Trinian's
Cite this Source
Firth and Arm. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/arm/firth
Arm & Firth. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/arm/firth>.
Firth or Arm. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/arm/firth.
Google Ngram Viewer shows how "arm" and "firth" have occurred on timeline