What does R stand for?

What does R mean?

R	Repose Community
R	Ramming Governmental » Military
R	Retentive Community » Educational
R	Rollicking Community » Music
R	Reigned Governmental
R	Resilience Academic & Science » Psychology
R	Rationality Academic & Science » Mathematics
R	Readability Community » Media
R	Rarity Miscellaneous » Coins
R	Rosy Miscellaneous » Colors
R	Reissue Miscellaneous » Hobbies
R	Respirations Medical » Physiology
R	Renormalization Academic & Science » Mathematics
R	Regular Army Governmental » Military
R	Rebelion Governmental » US Government
R	Retailer's price Business » General
R	Rumex Academic & Science » Botany
R	Rithmetic Community » Educational
R	Re-bill Business » Accounting
R	Recommitment Community » Religion
R	Rejoining Governmental » Military
R	Relaxed Medical » Physiology
R	Reencoding Computing » Security
R	Rebill Business » Accounting
R	Received solid signal Academic & Science » Amateur Radio