Meaning of “lean” - Learner’s Dictionary

lean

verb us uk /liːn/ past tense and past participle leaned, also UK leant /lent/
Extra Examples
Flint leaned back in his chair.She leaned forward to make sure I could hear her.He leaned across and took his ticket.He leaned closer so that his face was only inches from hers.She leaned down and kissed the child's head.
lean (sth) back/forward/out, etc

B2 to move the top part of your body in a particular direction:

She leaned forward and whispered in my ear.
He was leaning out of the window.
Lean your head back a bit.

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