The undulating , heaving motion of the sea , the swell , surge ; hence, meton. for the sea in agitation , waves , billows .

http://lila-erc.eu/data/lexicalResources/LewisShort/id/LexicalSense/n1404.3 an entity of type: LexicalSense

The undulating , heaving motion of the sea , the swell , surge ; hence, meton. for the sea in agitation , waves , billows . 
The undulating , heaving motion of the sea , the swell , surge ; hence, meton. for the sea in agitation , waves , billows . 

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