counterstamp

[ noun koun-ter-stamp; verb koun-ter-stamp ]
/ noun ˈkaʊn tərˌstæmp; verb ˈkaʊn tərˈstæmp /

noun

a stamp added to a stamped paper or document as a qualifying mark.
Numismatics. countermark(def 1).

verb (used with object)

to stamp (a paper or document) already stamped.
Numismatics. countermark(def 2).

Origin of counterstamp

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019