404: rip Jan 16, 2016
Many people know "RIP", if not from actual tombstones, then from the popularity of the word. Although it is similar, the acronym is not short for "rest in peace". Instead, the phrase is from the Latin tombstone-abbreviation for "requiēscat in pāce". 'Requiēscat' is formed from the verb meaning "rest", but it is subjunctive, and should be translated as “may s/he rest in peace”, which is somewhat kinder than an imperative command to be restful.