noun Date: 1786 a broad deep undulation of the ocean caused by an often distant gale or seismic disturbance, a rapid spontaneous growth (as of political opinion)
GROUNDSWELL
Meaning of GROUNDSWELL in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012