from
The Collaborative International Dictionary of English v.0.48
Sound \Sound\, n. [AS. sund a narrow sea or strait; akin to
Icel., Sw., Dan. & G. sund, probably so named because it
could be swum across. See {Swim}.] (Geog.)
A narrow passage of water, or a strait between the mainland
and an island; also, a strait connecting two seas, or
connecting a sea or lake with the ocean; as, the Sound
between the Baltic and the german Ocean; Long Island Sound.
[1913 Webster]
The Sound of Denmark, where ships pay toll. --Camden.
[1913 Webster]
{Sound dues}, tolls formerly imposed by Denmark on vessels
passing through the Baltic Sound.
[1913 Webster]