Noun po has 4 senses
- polonium, Po, atomic number 84 - a radioactive metallic element that is similar to tellurium and bismuth; occurs in uranium ores but can be produced by bombarding bismuth with neutrons in a nuclear reactor
--1 is a kind of metallic element, metal
- petty officer, PO, P.O. - a noncommissioned officer in the navy with a rank comparable to sergeant in the army
--2 is a kind of noncommissioned officer, noncom
--2 has particulars: master-at-arms
- Po, Po River - a European river; flows into the Adriatic Sea
--3 is a kind of river
--3 is a part of Italy, Italian Republic, Italia
- United States Post Office, US Post Office, Post Office, PO - an independent agency of the federal government responsible for mail delivery (and sometimes telecommunications) between individuals and businesses in the United States
--4 is a kind of independent agency
--4 has members: post office, local post office
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