Metaphysical meaning of Jashar (mbd)
Jashar (A. V., Jasher), ja'-shär (Heb.)--even; level; right; upright; uprightness; virtue; integrity; righteousness; Truth.
A book (Josh. 10:13; II Sam. 1:18). Fallows says, "As the word Jasher signifies just or upright, by which word it is rendered in the margin of our Bibles, this book has been generally considered to have been so entitled as containing a history of just men."
Meta. The phase of our memory that retains thoughts that are just, righteous, and true.