p.m.       
abbreviation uk/ˌpiːˈem/ us/ˌpiːˈem/
A1 下午
used when referring to a time in the afternoon or evening or at night
  We'll be arriving at about 4.30 p.m.  我们下午4:30左右到。 
 The 6 p.m. train is usually very crowded. 下午6点的火车通常很挤。 
 Compare: a.m.
 - More examples
 - The moon will be totally eclipsed at 12.10 p.m.
 - The exact time of the accident was 2.43 pm.