B1
the middle part of your leg where it bends
Dictionary examples:
I accidentally kissed my knee instead of the football for good luck. (0.0)
My knee has a mind of its own during boring meetings. (0.0)
I tried to teach my knee to behave during important presentations. (0.0)
a knee injury (34.1)
The baby was crawling around on its hands and knees. (41.8)
He got/went down on his knees in front of the altar. (56.0)