From Longman Dictionary of Contemporary Englishstamp somebody as something phrasal verbCHARACTER/PERSONALITYto show that someone has a particular type of character It was his manners that stamped him as a real gentleman. → stamp→ See Verb table
Examples from the Corpus
stamp as • On the surface, the veneer of an open democratic debate; underneath, the potential of a pre-determined rubber stamp.• To stamp her feet as a child again.• Y., collected stamps and, as a high school honors student, performed science experiments on the conductivity of seawater.• These stamps are described as definitives by the Postal Service which means they should be regularly stocked by most post offices.• One cradled a paper cup of coffee in both hands, stamping his feet as if it was cold.• Then my father would light a candle and we would all swat, stamp and squash as many as we could.• Others shuffled and stamped their feet as the cold from the frosted pavement penetrated the thin soles of their shoes.• Some Republicans are trying to stamp him as unpatriotic.• It boasts a post box, stamp machine as well as an A/B button telephone. 