PO

An acronym that comes from the Latin phrase "per os," which means "by mouth;" commonly seen in medical prescriptions when used by a doctor to indicate how a medication should be taken; often appears as "p.o."

A baseball abbreviation for putout that refers to the number of outs recorded by a defensive player; achieved by a fielder who tags out a runner, tags a base while in possession of a ball for a force out, catches a ball batted in the air, catching a third strike, and is closest to a runner called out for interference.