| ARS | • ars n. Plural of ar. • ARs n. Plural of AR. • ARS n. Initialism of acute radiation syndrome. |
| ERS | • ers v. Third-person singular simple present indicative form of er. • ERs n. Plural of ER. • ERS n. (Sports, automotive) Acronym of energy recovery system: an electric generation, storage, and propulsion… |
| ORS | • ors n. Plural of or. • Ors prop.n. Plural of Or. • ORs n. Plural of OR. |
| RAS | • ras n. An Ethiopian king or prince. • ras n. A headland; a cape. • Ras prop.n. A surname. |
| RES | • res n. Plural of re. • res n. (North America, informal) Clipping of reservation. • res n. (Canada, South Africa) Clipping of residence. |
| SAR | • Sar prop.n. A surname from Khmer. • SAR n. Acronym of search and rescue. • SAR n. (Aerospace) Acronym of synthetic-aperture radar. |
| SER | • ser n. Abbreviation of serial. • ser n. (In some fantasy and sci-fi novels) An address or courtesy title to any person, especially if their… • Ser n. (Biochemistry) IUPAC 3-letter abbreviation of serine. |
| SIR | • sir n. A man of a higher rank or position. • sir n. A respectful term of address to a man of higher rank or position, particularly… • sir n. A respectful term of address to an adult male (often older), especially if his name or proper title is unknown. |
| SRI | • Sri n. Alternative form of Shri. • SRI prop.n. Initialism of System of Rice Intensification. • SRI n. Abbreviation of socially responsible investment. |
| SUR | • SUR sym. (International standards) ISO 3166-1 alpha-3 country code for Suriname. • SUR sym. (International standards, historical) ISO 4217 currency code for the former sixth Soviet ruble; a currency… • sur- pref. (Not currently productive) A syncopic variant of super-. |