from Latin commonstrāt- ppl. stem of commonstrāre, from com- + monstrāre to show
1623 - The English Dictionarie, or an Interpreter of hard English Words, Henry Cockeram;
"Commonstrate, to teach"
From: A Medicinal Dispensatory: Containing the Whole Body of Physick
Composed by the Illustrious Renodæus,
Chief Physician to the Monarch of France,
and now Englished and Revised,
By Richard Tomlinson of London, Apothecary, 1657