esr

(noun) the rate at which red blood cells settle out in a tube of blood under standardized conditions; a high rate usually indicates the presence of inflammation. Synonyms: erythrocyte sedimentation rate, ESR, sedimentation rate, sed rate.

(noun) microwave spectroscopy in which there is resonant absorption of radiation by a paramagnet. Synonyms: electron spin resonance, ESR, electron paramagnetic resonance.