o ‧ ver ‧ val ‧ ue /ˌəʊvəˈvæljuː $ ˌoʊvər-/ BrE AmE verb [transitive]
[ Word Family: noun : ↑ valuables , ↑ value , values, ↑ valuation , ↑ valuer , ↑ overvaluation ≠ UNDERVALUATION , ↑ devaluation ; adjective : ↑ valuable , ↑ invaluable , overvalued ≠ UNDERVALUED , ↑ valueless , ↑ valued ; verb : ↑ value , ↑ devalue , ↑ overvalue ≠ ↑ undervalue ]
to believe or say that something is more valuable or more important than it really is
—overvaluation /ˌəʊvəvæljuˈeɪʃ ə n $ ˌoʊvər-/ noun [uncountable]