In reading "Two Years Before the Mast" Dana, in telling about sailors aloft, mentioning the "bunt" of the sail.
I had heard "bunt" being used for goat butting. Naturally, I had heard about baseball "bunt" meaning to just hold bat motionless to meet the pitch. My mother was brought up in Belfast, ME, a seaport, and used quite a few sailor words.
When there was a crust on the snow, we could just lie down
on our stomachs and slide without a sled. She called that
"belly bunt". I just now disovered that it means the curving belly of some big fish. That may have influeced the description of a "bellying" of a big square sail as the bunt of the sail.
bunt 1
vt., vi.
5< ? ME bounten, to return6
1 [Brit. Dial.] to strike or butt with or as with horns
>2 Baseball to bat (a pitched ball) lightly without swinging so that it rolls within the infield, usually in attempting to advance a base runner
n.
1 a butt or shove
>2 Baseball a) the act of bunting b) a bunted ball

bunt 2
n.
5< earlier dial., a puffball6 a disease that destroys the grain of wheat and other grasses, caused by various fungi (genus Tilletia)

bunt 3
n.
5< ? MLowG & MDu, a binding, bundle; akin to BIND6
1 the sagging part of a fish net
2 the bellying part of a square sail