B1
a single thing or a separate part of something larger
Dictionary examples:
The teacher called our class 'the most talkative unit' she's ever taught. (0.0)
The pizza delivery guy got lost in our apartment unit maze. (0.0)
My phone is like a separate unit attached to my hand now. (0.0)
Each unit of the course book focuses on a different grammar point. (29.9)
The first year of the course is divided into four units. (34.7)