ox·im·e·ter (?k-s?m??-t?r)n. A device for measuring the oxygen saturation of arterial blood, especially a pulse oximeter.ox?i·met?ric (-m?t?r?k) adj.ox?i·met?ri·cal·ly adv.ox·im?e·try n.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.oximeter (?k?s?m?t?) n (Medicine) med an instrument for measuring oxygen in bloodCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014