means Having a circular or spherical form, free of angles; also, by extension, a complete cycle or a sum without fractions.

from From Old French 'reond' (later 'rond'), descended from Latin 'rotundus' meaning 'wheel-shaped,' which itself spins out of 'rota,' a wheel — the same root that rolls into 'rotate,' 'rotund,' and 'roundabout.' The Latin idea was always motion and circularity, the wheel that turns back to where it began, which is why a 'round' can mean a circle, a cycle of drinks, or a full revolution of the seasons.