DISCERNER n.
One who, or that which, discerns, distinguishes, perceives, or judges; as, a discerner of truth, of right and wrong. A great observer and discerner of men's natures. Clarendon.
DISCHARGER n.
One who, or that which, discharges. Specifically, in electricity, an instrument for discharging a Leyden jar, or electrical battery, by making a connection between the two surfaces; a discharging rod.