2. (Zo["o]l.)
(a) Any tern of the genus {Anous}, as {A. stolidus}.
(b) The arctic fulmar ({Fulmarus glacialis}). Sometimes
also applied to other sea birds.
3. An old game at cards. --Halliwell.
4. A small two-wheeled one-horse vehicle.
5. An inverted pendulum consisting of a short vertical flat
spring which supports a rod having a bob at the top; --
used for detecting and measuring slight horizontal
vibrations of a body to which it is attached.