Polarograph

[ poh-lar-uh-graf, -grahf, puh- ]
/ poʊˈlær əˌgræf, -ˌgrɑf, pə- /

Trademark.

a brand name for an instrument that automatically registers the current in electrolysis at a dropping mercury electrode.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019