Lassitude:Weakness, weariness, listlessness, exhaustion,lethargy. For example, the patient complained oflassitude. From Latin lassitudo, from lassus meaning weary. From Healthy Resources 10 Rheumatoid Arthritis Symptoms What Is Exocrine Pancreatic Insufficiency? Life With RRMS: A Shift in Positivity Featured Centers What Are the Best PsA Treatments for You? Understanding Biologics 10 Things People With Depression Wish You Knew Health SolutionsFrom Our Sponsors