postage meter
noun🔊/ˈpəʊstɪdʒ miːtə(r)/
🔊/ˈpəʊstɪdʒ miːtər/
(North American English) (also franking machine especially in British English)
a machine that prints an official mark on a letter to show that the cost of posting it has been paid, or does not need to be paid 邮资机（加盖邮资已付印记）