lin·e·a as·pe·ra 
(lĭnē-ə ăspə-rə)
(lĭnē-ə ăspə-rə)n. pl. lin·e·ae as·pe·rae (lĭnē-ē′ ăspə-rē′)
A longitudinal ridge running down the posterior surface of the shaft of the femur, affording attachment to various muscles.
[New Latin līnea aspera, rough line : Latin līnea, line; see LINE + Latin aspera, feminine of asper, rough (in reference to its rough texture).]