Fetching details from the dictionary...

whole year; all year round; throughout the year
always; all the time; perpetually
during an era
second-year kindergarten student
この店は年じゅう無休で営業している。
This shop is open year-round without any holidays.
沖縄は年じゅう暖かい気候が続く。
Okinawa has warm weather all year long.
花が年じゅう咲いている。
Flowers are blooming all year round.