The Collaborative International Dictionary of English v.0.48:
Overvalue \O`ver*val"ue\, v. t. [imp. & p. p. Overvalued; p. pr. & vb. n. Overvaluing.] 1. To value excessively; to rate at too high a price. "To overvalue human power." --Holyday. [1913 Webster] 2. To exceed in value. [R.] --H. Brooke. [1913 Webster]