SAR may stand for: Science in taxonomy, a proposed supergroup containing the Chromalveolata and the Rhizaria, standing for the three largest groups within these: Stramenopiles, Alveolata, Rhizaria in microbiology, a naming convention for uncultured bacteria first found in the Sargasso Sea (see SAR11) in pharmacology and medicinal / computational chemistry, structure-activity relationship regarding plant disease, Systemic acquired resistance Seasonal allergic rhinitis Sexual Attitude Reasse… (More on Sar)