Lewis Short
rectĭtūdo (noun F) : rectus (post-class.).
* Straightness, directness.Lit., Aggen. ap. Front. p. 46 Goes.
* Trop., uprightness, rectitude (class. aequitas), Hier. in Isa. 8, 10; 26, 7: hominum,Just. Nov. 13 praef.
Charlton T. Lewis, Charles Short, A Latin Dictionary