R.H.
Royal Highlanders 英国野戦砲兵隊;Royal Highness
R.I.1
Republic of Indonesia インドネシア共和国;Rhode Island;Royal Institute [Institution] 英国王立科学研究所
R.I.2
Regina et Imperatrix 女王兼女帝(Queen and Empress);Rex et Imperator 国王兼皇帝(King and Emperor)語源[ラテン]
R.I.P.
安らかに眠れ(May he [she] rest in peace)語源[ラテン requiescat in pace]
R.P.
received pronunciation;Reformed Presbyterian 改革派長老会;Regius Professor
R.Q.
《生理》respiratory quotient
R.R.
((米))Railroad;Right Reverend;rural route
R.W.
Right Worshipful [Worthy] 閣下(◆敬称)
R/D
refer to drawer (手形などの)振出人回し
R/W
《コンピュ》Read/Write