D defs.my
Entry 2 senses Webster, 1913

groundswell

/(ground"swĕl`)/ · ground·swell · IPA /ɡrˈaʊndswˌɛl/
01 n. A long, deep wave in the sea, sometimes caused by distant winds or storms.
  1. 1.
    A long, deep wave in the sea, sometimes caused by distant winds or storms.
  2. 2.
    A rising sentiment of support or enthusiasm, especially among the general public; as, a groundswell of opinion favoring campaign finance reform.