Definition of "P"

P¹

letter
upper case, lower case p, plural Ps or P's
1. The sixteenth letter of the English alphabet, called pee and written in the Latin script.
number
upper case, lower case p
1. The ordinal number sixteenth, derived from this letter of the English alphabet, called pee and written in the Latin script.

P²

/piː/

noun
plural Ps
1. Abbreviation of park.
2. Abbreviation of phone.
3. Abbreviation of pager.
4. Abbreviation of passenger.
5. Abbreviation of pocket.
6. Alternative form of ₱ (Philippine peso)
7. (chess) Abbreviation of pawn.
8. (medicine) A P wave on an electrocardiogram.
9. (slang, chiefly US) Abbreviation of pure (A "pure" form of an illegal drug, especially heroin).
  Quotations
  P directly targets the dopamine pathways in your brain and as a result goes straight to your pleasure/reward module, which makes it an incredibly hard drug to break free from.
  2009, Dr Kerry Spackman, The Winner's Bible
10. (slang, New Zealand) Abbreviation of pure (A "pure" form of an illegal drug, especially methamphetamine).
  Quotations
  Almost 70kg of pre-cursor drugs that could be used to manufacture $20 million of P have been seized by police and customs officers.
  2011 May 6, New Zealand Herald
11. (UK, television) Initialism of product placement. (displayed on screen as an indicator to viewers)
adjective
not comparable
1. (UK) Abbreviation of probationary (used on a vehicle's P-plate)
2. (Australia) Abbreviation of provisional (used on a vehicle's P-plate)
3. (anatomy, medicine) Abbreviation of pulmonary.
adverb
not comparable
1. (chiefly US) Alternative spelling of P.M. (“post meridiem”) or PM
proper noun
1. (computing theory) The set of all problems that are solvable in polynomial time by a deterministic Turing machine
2. (law) Initialism of patient. (the subject of proceedings in the Court of Protection)
3. (biblical, history) Abbreviation of Priestly source.