p.a. > define

noun

• An electronic amplification system used as a communication system in public areas.
  • synonyms: public address system, P. A. System, PA system, PA

adverb

• By the year; every year (usually with reference to a sum of money paid or received. )
  • usage: "he earned $100, 000 per annum"; "we issue six volumes per annum"
  • synonyms: per annum, per year, each year, annually

(latin) p.a. - through a year