13
inlet(noun, sound, opening, box, arm)
11
bay(noun, sound, retreat, arm, dock)
11
gulf(noun, sound, arm, sea, mouth)
10
cove(noun, sound, course, arm, channel)
9
frith(noun, bay, gulf, inlet, gulf lake)
9
loch(noun, bay, gulf, inlet, cove)
7
estuary(noun, sound, opening, box, entrance)
6
bight(noun, sound, arm, mouth, harbor)
6
fjord(noun, sound, channel, mouth, outlet)
6
mouth(noun, opening, arm, entrance, outlet)
5
bayou(noun, sound, arm, bay, mouth)
5
sound(noun, channel, bay, mouth, harbor)
4
arm(noun, sound, water, channel, mouth)
4
creek(noun, sound, arm, channel, bay)
4
fiord(noun, gulf lake)
4
harbor(noun, place, sound, opening, box)
4
harbour
4
lagoon(gulf lake, body of water)
4
sea loch(noun, bay, gulf, inlet, cove)
4
strait(noun, sound, channel, haven, mouth)
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APASmart Define. (2015). firth thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/firth/thesaurus/synonyms
ChicagoSmart Define. 2015. "firth thesaurus" https://smartdefine.org/firth/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, firth thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/firth/thesaurus/synonyms>.
MLASmart Define. "firth thesaurus" 10 April 2015. Web. 20 September 2026. <https://smartdefine.org/firth/thesaurus/synonyms>