(intransitive, followed by "over") to collapse, to fall
To traverse with a keel; to navigate.
To turn up the keel; to show the bottom.
Esimerkit
He keeled over after having a stroke.
"Then the steersman took his place at the right of the sternpost, looking forward to the ship's master, who stood on a plank let in at the jointure of the keel with the stem, which was carved as the Old Serpent of Andrad."