good morning
exclamation /ˌɡʊd ˈmɔːnɪŋ/
  /ˌɡʊd ˈmɔːrnɪŋ/
 (also informal morning)
- used to say hello politely when people first see each other in the morning; sometimes also used formally when people leave each other in the morning- He didn't even say ‘Good morning’.