Good evening. What are you doing in a place like this?
"Oh hey, good evening." "Good evening." "How was the meeting with the president yesterday?" "Well, I was certain I would be promoted, but I was fired instead."
Good evening, Uncle Koichi. Thank you for taking care of our baby today. Hey, you didn’t microwave that, did you? Because it’s breast milk, you’re not supposed to do that.
This word is made of now and night with the hiragana は at the end. The は here is pronounced as わ (the old pronunciation). When you say "now night!" you're really saying good evening.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well. Just be aware that the は at the end is actually the particle は so it's pronounced like わ.