noun Etymology: Middle English kelswayn, probably of Scandinavian origin; akin to Swedish kölsvin ~ Date: 13th century a longitudinal structure running above and fastened to the keel of a ship in order to stiffen and strengthen its framework
KEELSON
Meaning of KEELSON in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012