Definition of "AR"

(statistics) Initialism of autoregressive.  examples

(countable, weaponry) an AR-15 personal semi-automatic rifle, M-16 assault rifle, M-4 carbine, derivative or related gun; the Armalite AR family and derivatives.  examples

(countable, weaponry, informal) an assault rifle or automatic rifle.  examples

(biochemistry) Initialism of androgen receptor.  examples

(accounting, uncountable or plural only) Initialism of accounts receivable.  examples

(sports, countable) area record: best achievement among those by persons from a given continent  examples

(sports, US, countable) Abbreviation of American record., national record for the United States.  examples

(crime) Initialism of armed robbery.  examples

(computing, chiefly uncountable) Initialism of augmented reality.  examples

(countable) Initialism of aspect ratio.  examples

(fan fiction) alternate reality  examples

(meteorology) Initialism of atmospheric river.

(emergency medicine) Initialism of artificial respiration.  examples

(philately, postal service) Initialism of acknowledgment of receipt.  examples

(law, politics) Initialism of assembly resolution.  examples

Initialism of administrative rule or administrative regulation.  quotations  examples

Postal abbreviation of Arkansas  examples

Abbreviation of Arunachal Pradesh. (a state of India)  examples