a simpleton; a fool.-any tern of the genus anous, as a. stolidus.-the arctic fulmar (fulmarus glacialis). sometimes also applied to other sea birds.-an old game at cards.-a small two-wheeled one-horse vehicle.-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.