n. [ Mega- + -meter: cf. F. mégamètre. ] (Physics) 1. An instrument for determining longitude by observation of the stars. [ 1913 Webster ]
2. A micrometer. [ R. & Obs. ] Knight. [ 1913 Webster ]
{ } n. [ Mega- + meter, metre, n., 2. ] In the metric system, one million meters, or one thousand kilometers. [ 1913 Webster ]