a.m.

名词 a.m.:

1. a radioactive transuranic metallic element; discovered by bombarding uranium with helium atoms
   同义词：americium, Am, atomic number 95
2. a master's degree in arts and sciences
   同义词：Master of Arts, MA, Artium Magister, AM
3. modulation of the amplitude of the (radio) carrier wave
   同义词：amplitude modulation, AM

形容词 a.m.:

1. before noon
   同义词：ante meridiem

副词 a.m.:

1. before noon
   同义词：ante meridiem