ti·sane (t?-z?n?, -zän?)n. An herbal infusion or similar preparation drunk as a beverage or for its mildly medicinal effect.[French, barley water, from Old French, from Latin ptisana, tisana; see ptisan.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.tisane (t??zæn) n (Cookery) an infusion of dried or fresh leaves or flowers, as camomile[C19: from French, from Latin ptisana barley water; see ptisan]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014ti?sane (t??zæn, -?z?n) n. a decoction of herbs usu. drunk for medicinal purposes. [1930?35;