Etymology of the Latin word anesthesia
the Latin word anesthesia
derived from the Greek word anaisthesia, ἀναισθησία, ἀναισϑησία
derived from the Greek word aisthesis, αἴσθησις (sensation; perception; discernment)
derived from the Greek word aisthanomai, αἰσθάνομαι (to apprehend (properly, by the senses))
using the Medieval Greek prefix an-, ἀν-