undertriage noun 1verb 1forms 3 noun1 •An inaccurately low prehospital triage value assigned to a set of symptoms or an injury, assessing it as being less severe or traumatic than it truly is; the administrative or societal burden caused by such miscalibration, such as strokes or heart attacks not recognized and treated quickly enough.However, our prior study on undertriage of major trauma patients indicated that a significant proportion of trauma patients with an ISS = 75 survived. — 2015 verb1 •To make such a misguided triage assessment. formsundertriaged · undertriaging · undertriages