In this short intervention the author analyzes the attestations of the Polish coins that circulated in the Romanian space. Since they are relatively numerous, it has stopped on one of them, namely the ”potronic”. Potronic is a word certified especially on the territory of Moldova and less in the other Romanian provinces to designate a divisional silver coin commonly used in various transactions or the payment of taxes and duties, which is why this currency denomination benefits from an extended documentary fund. Relative to the issue of the origin of the name of this coin, the proposed and accepted etymology is potrojnik (po + trojnik) which in Polish means ”three” or ”triple” (meaning coin of three groszy) and which in the Romanian numismatic literature came under the name of troyak (= trojaki). The significant presence of this coin, suggestively exemplified both literally and archeologically, is not an exception, but on the contrary confirms historical realities this numeral filling to some extent the lack of cash on the Romanian market.