a combining form meaning “walking, moving,” in the manner or by the means specified by the initial element: plantigrade.
Origin of -grade
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
adj combining form
indicating a kind or manner of movement or progressionplantigrade; retrograde
Word Origin for -grade
via French from Latin -gradus, from gradus a step, from gradī to walk
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012