Meaning of “rear” - Learner’s Dictionary

rear

noun uk us /rɪər/
the rear

the back part of something:

First class accommodation is towards the rear of the train.
bring up the rear

to be at the back of a group of people who are walking or running

rear adjective [ always before noun ]

B2

a rear window/wheel

(Definition of “rear noun” from the Cambridge Learner’s Dictionary © Cambridge University Press)