Definition of "ARP"

ARP

noun
countable and uncountable, plural ARPs
1. (physiology) Initialism of absolute refractory period.
2. (British, dated) Short for Air Raid Precautions.
  Quotations
  The small white squares painted above the footboard at the ends of S.R. passenger coaches were a wartime addition to show that the lighting arrangements of vehicles so marked had been altered to conform to A.R.P. regulations.
  1946 September and October, “The Why and The Wherefore: A.R.P. Coach Lighting Regulations”, in Railway Magazine, page 325
proper noun
1. (networking, Internet) Initialism of Address Resolution Protocol.