- A small constellation north of Aquila; the Arrow. - The keystone of an arch. - The distance from a point in a curve to the chord; also,
the versed sine of an arc; -- so called from its resemblance to an
arrow resting on the bow and string. - The larger of the two otoliths, or ear bones, found in
most fishes. - A genus of transparent, free-swimming marine worms having
lateral and caudal fins, and capable of swimming rapidly. It is the
type of the class Chaetognatha.
Definition
[ n.]