Hello, I am a Japanese. mmm, this word is difficult to explain. It has two meanings. ごきげんよう=How are you? ごきげんよう=Have a good day! When you meet someone, you can say 「ごきげんよう」 When you say goodbye to someone, you can say「ごきげんよう」 Probably, the latter pattern is more popular than the former one.