Κλεάνθης (Ancient Greek) comes from Ancient Greek κλέος, from Proto-Hellenic kléwos, from Proto-Indo-European ḱléwos, from Proto-Indo-European ḱlew-, from Proto-Indo-European ḱel- — to cover; to incline.
Ancestry of “Κλεάνθης”, step by step
Κλεάνθης traces back through two separate lines of ancestry.