adj : having two phases: as a : exhibiting a stage of stimulation followed by a stage of depression or vice versa <the action of certain drugs> b : relating to or being a record of a nerve impulse that is negative and positive <a action potential> - compare MONOPHASIC1 POLYPHASIC1 .
action of certain drugs> b : relating to or being a record of a nerve impulse that is negative and positive <a 
