Editing Pa (section)

== Science and technology==
* [[.pa]], top-level domain for Panama
* [[ALCO PA]], a railroad locomotive
* [[Parental alienation]], in psychology
* [[Pascal (unit)]], the SI unit of pressure
* [[Peano axioms]], a set of axioms for the natural numbers
* [[Peptide amphiphile]], a type of self-assembling peptide
* [[Picoamp]] (pA), one trillionth of an ampere
* [[Polyacrylamide]], a gel-forming polymer
* [[Polyamide]], a family of synthetic materials used in fabrics
* [[Predictive analytics]], analyzes current and historical facts to make predictions about future or otherwise unknown events
* [[Protactinium]], symbol Pa, a chemical element
* [[Provider-aggregatable address space]], a system of allocation of internet addresses
* [[Public address system]] (PA system or simply PA), for making public announcements
* [[Pernicious anemia]], anemia that results from lack of intrinsic factor
* [[Primary aldosteronism]], excess production of the hormone aldosterone from the adrenal glands