when calling in rx what does tid mean
The term PO TID on a doctor's prescription or order would mean: by mouth, three times daily. PO means by mouth. This medical abbreviation, which is also written as: p.o. â¦ or po (lower case), comes from the Latin phrase per os. The term TID means three times daily, or three times per daily. This medical abbreviation, which is also written as: t.i.d. or tid (lower case), comes from the later phrase ter in die. What does taking a medication po tid mean?