PO
Abbreviation with 13 meanings
| Stands for | Per os (by mouth, orally) |
|---|---|
| Meanings | 13 |
| Categories | Medical, Business & Finance, Government & Politics, Writing & Everyday, Military, Science & Engineering, Law & Legal, Sports |
| Also written | Po |
PO has 13 meanings. The most common are Per os (by mouth, orally) (medication route) and Purchase order (accounting); it can also stand for Parole officer, Police officer, Probation officer, Post office and Petty Officer, plus 6 more listed below.
Meanings of PO at a glance
| # | PO stands for | Context |
|---|---|---|
| 1 | Per os (by mouth, orally) | Medical › Medication Route |
| 2 | Purchase order | Business & Finance › Accounting |
| 3 | Parole officer | Government & Politics › Police |
| 4 | Police officer | Government & Politics › Police |
| 5 | Probation officer | Government & Politics › Police |
| 6 | Post office | Writing & Everyday › Mail and Postal |
| 7 | Petty Officer | Military › US Navy and Coast Guard Rank |
| 8 | Polonium | Science & Engineering › Chemical Element |
| 9 | Product owner | Business & Finance › Project Management |
| 10 | Probation officer or parole officer | Law & Legal › Criminal Law |
| 11 | Protective order | Law & Legal › Litigation |
| 12 | Postal order | Writing & Everyday › Mail and Postal |
| 13 | Putout | Sports › Baseball |
1. Per os (by mouth, orally)
Medical · Medication Route Abbreviations
The oral route: the medicine is swallowed and absorbed through the digestive tract. Tablets, capsules, liquids and suspensions are given PO, and absorption can be affected by food, stomach acid and first-pass metabolism in the liver.
Example: Switch levofloxacin 750 mg IV to PO once tolerating diet.
From Latin "per os", "through the mouth"; also written p.o. or po. ISMP lists the spelled-out phrase "per os" as error-prone because "os" can be read as OS (left eye), so it recommends "PO", "by mouth" or "orally". Hospital pharmacists run IV-to-PO conversion programs because oral drugs with high bioavailability, such as levofloxacin and linezolid, work as well as IV forms at lower cost.
2. Purchase order
Business & Finance · Accounting Abbreviations
Document a buyer issues to a supplier authorizing a purchase and specifying items, quantities, prices, delivery terms and payment terms. Once accepted, it forms a binding contract, and it is matched with the delivery receipt and invoice before payment.
Example: Invoices without a valid PO number will be returned to the supplier unpaid.
Many companies enforce a "no PO, no pay" policy to control spending. A blanket PO covers repeated purchases over a period, such as office supplies. In ERP systems the PO links procurement to accounts payable through the three-way match. PO also means post office and, in medicine, by mouth.
3. Parole officer
Government & Politics · Police Abbreviations
Officer who supervises people released from prison on parole, enforcing conditions such as reporting, drug testing, residence and employment. Parole officers usually work for a state corrections department or parole board.
Example: He has to meet his PO every Tuesday and can't live within 1,000 feet of a school.
Parole is conditional release before the end of a prison sentence. The federal system largely abolished parole for offenses committed after 1987, replacing it with supervised release overseen by probation officers. Parole violations can send a person back to prison.
4. Police officer
Government & Politics · Police Abbreviations
Title and abbreviation for a uniformed officer, used in reports, court papers and name plates; in the NYPD the entry rank is formally "Police Officer," abbreviated P.O. before a name.
Example: P.O. Ramirez testified that she saw the defendant drop the bag as he ran.
Police officer replaced "patrolman" in many US departments from the 1970s as women joined patrol ranks. Court reporters and news stories often write "Police Officer" in full the first time and PO after. Context separates it from probation officer and parole officer, which share the initials.
5. Probation officer
Government & Politics · Police Abbreviations
Court or county officer who supervises people sentenced to probation instead of prison, checking compliance with conditions such as drug testing, employment, curfews and treatment. Probation officers write presentence reports for judges.
Example: My PO said I can't leave the county for the wedding without written permission.
Probation is a sentence imposed by a court, usually in place of incarceration, while parole follows release from prison. Probation officers may work for courts, counties or states, depending on the jurisdiction. Violating probation conditions can lead to a VOP hearing and jail.
6. Post office
Writing & Everyday · Mail and Postal Abbreviations
Refers to a post office, the local facility that handles mail, sells stamps and holds post office boxes. It also forms part of compounds such as PO Box.
Example: I need to stop by the PO to mail this package before it closes at 5.
The US Postal Service runs more than 30,000 post offices. In the United Kingdom, the Post Office counter network has been a separate company from Royal Mail since 2012. In business, PO more often means purchase order, so context matters.
7. Petty Officer
Military · US Navy and Coast Guard Rank Abbreviations
Generic title for Navy and Coast Guard enlisted members in pay grades E-4 to E-6, the naval equivalent of noncommissioned officers. Petty officers lead work centers, stand qualified watches and train junior sailors, with class shown by one to three chevrons under an eagle.
Example: Report to the duty PO at the quarterdeck before going ashore.
"Petty" comes from Anglo-Norman "petit," small, marking these as minor officers in the age of sail. The Royal Navy uses the same title for its OR-6 rank. In formal writing the class is given (PO1, PO2, PO3), while in Navy practice the rate with rating is preferred, such as YN1 instead of PO1.
8. Polonium (Po)
Science & Engineering · Chemical Element Abbreviations
Intensely radioactive, polonium (atomic number 84) emits alpha particles so energetically that a small sample glows and warms itself. Polonium-210 is used in antistatic brushes and was used to poison former Russian security officer Alexander Litvinenko in London in 2006.
Example: Static eliminators for film cleaning contain a sealed Po-210 strip that must be replaced every year.
Marie and Pierre Curie announced polonium in July 1898, months before radium, after extracting it from tons of pitchblende. Marie named it after her homeland, Poland, which at the time was partitioned among Russia, Prussia and Austria. Polonium-210 has a half-life of 138 days and occurs in small amounts in tobacco smoke.
9. Product owner
Business & Finance · Project Management Abbreviations
Scrum role accountable for maximizing the value of the product, mainly by creating, ordering and clarifying the product backlog and deciding what the team works on next.
Example: Ask the PO whether the export feature beats the dashboard fix in priority.
The Scrum Guide insists the product owner is one person, not a committee, though they may represent many stakeholders. The role differs from a product manager, although one person often does both. In purchasing, PO means purchase order.
10. Probation officer or parole officer
Law & Legal · Criminal Law Abbreviations
Officer who supervises people serving probation or parole in the community, enforcing conditions such as drug testing, employment, curfews and treatment, and reporting violations to the court or parole board. Probation officers also prepare presentence reports.
Example: My PO approved the job, but I still have to check in every two weeks.
Probation is imposed by a court instead of or after jail, while parole follows release from prison under a parole board's authority; federal supervised release is overseen by US probation officers. Supervisees can be searched under conditions upheld in cases such as United States v. Knights (2001). In civil litigation, PO means protective order.
11. Protective order
Law & Legal · Litigation Abbreviations
Court order in civil litigation limiting how discovery material may be used or disclosed, or shielding a party from burdensome or improper discovery. Stipulated protective orders let parties designate trade secrets and personal data as confidential.
Example: Documents marked confidential under the PO may be used only for this litigation and must be returned at the end.
Authorized by Federal Rule 26(c) on a showing of good cause. Many protective orders have two tiers: "Confidential" and "Highly Confidential – Attorneys' Eyes Only" (AEO). In family and criminal courts, a protective order instead protects a person from abuse or harassment. In business, PO usually means purchase order.
12. Postal order
Writing & Everyday · Mail and Postal Abbreviations
Refers to a British postal order, a money order bought at a Post Office counter and sent by mail to pay a named recipient. It was once a standard way to pay for mail-order goods and competition entries.
Example: Payment by cheque or PO only, made payable to the club treasurer.
British postal orders were introduced in 1881 and remain available, though online payments have largely replaced them. They are cashed or paid into a bank account by the named payee. The American equivalent is a postal money order sold by USPS.
13. Putout
Sports · Baseball Abbreviations
Fielding credit given to the player who completes an out by catching a fly ball, tagging a runner or touching a base. First basemen and catchers record the most putouts.
Example: The catcher recorded 13 PO, mostly on strikeouts.
Catchers receive a putout on every strikeout they complete. Putouts and assists together form the basis of the traditional fielding percentage. In military and general use, PO stands for purchase order or post office.
Related abbreviations
More medication route abbreviations
- OS – Oculus sinister (left eye)
- OU – Oculus uterque (each eye, both eyes)
- PCA – Patient-controlled analgesia
- PCEA – Patient-controlled epidural analgesia
- PR – Per rectum (rectally)
- PV – Per vaginam (vaginally)
- SC – Subcutaneous
- SL – Sublingual
See all 41 medication route abbreviations →
More accounting abbreviations
- P&L – Profit and loss statement
- PAT – Profit after tax
- PBT – Profit before tax
- PCAOB – Public Company Accounting Oversight Board
- PP&E – Property, plant and equipment
- PPA – Purchase price allocation
- PY – Prior year
- Q1 – First quarter
See all 95 accounting abbreviations →
This entry is for general education and is not medical or legal advice. Abbreviation use varies between institutions; always confirm in context.