short-acting

the compound adjective 'short-acting' is a modern formation in scientific and medical english, built from two native english elements. the first element, 'short', descends from proto-germanic skurtaz, conveying the concept of a brief temporal span. the second element, 'acting', derives from the latin verb 'agere', meaning to set in motion or to do, which entered english via french. in this compound, 'acting' functions as an adjective meaning 'producing an effect'. the logic of the word is transparently literal: something that 'acts' for a 'short' period. it is specifically applied in pharmacology to describe drugs whose therapeutic effects are rapid in onset and of limited duration, contrasting with 'long-acting' formulations.

Structure: short (brief) + acting (having an effect) short: from old english 'sceort', of germanic origin; meaning 'not long' or 'brief in duration'. acting: from latin 'actus', past participle of 'agere' (to do, to drive); the -ing suffix forms the present participle/adjective meaning 'performing the action of'.