hallmark UK /ˈhɔːlmɑːk/US /ˈhɔlmɑɹk/noun 2verb 1forms 3phrases 1 noun2 •An official marking made by a trusted party, usually an assay office, on items made of precious metals.It can highlight our embodiment, a qualitative step away from the hallmark machines that work so resolutely to disembody us. — 2007 •(figurative) A distinguishing characteristic.You know what a university is, and a university degree? It is the necessary hallmark of a man who wants to do anything in teaching. — 1894 verb1 •To provide or stamp with a hallmark.The cane was undoubtedly of foreign make, for it had a solid silver ferrule at one end, which was not English hall–marked. — 1904 formshallmarked · hallmarking · hallmarks Phrases with hallmark Hallmark momentA memorable moment or event, one which would either make for or call for a poignant greeting card.