The Next Month
Next Month, The Following Month
The next moon refers to the next month.
よくげつ
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.
彼は翌月黄色いドアがある小さな家に引っ越しています。
He is moving to the small house with the yellow door next month.