a noncommissioned officer in the Navy or Coast Guard with a rank comparable to sergeant in the Army;
Synonyms: petty officer / P.O.
po (n.)
an independent agency of the federal government responsible for mail delivery (and sometimes telecommunications) between individuals and businesses in the United States;
Synonyms: United States Post Office / US Post Office / Post Office
2
Po (n.)
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;