Most clean; the greatest degree of cleanliness in a group or comparison.
From 'clean' + superlative suffix '-est,' or from 'cleanly' + '-est.' The superlative form emerged to describe the most spotless version of something.
In the 1800s, cities held 'cleanliest street' competitions—it sounds trivial, but these contests genuinely drove civic improvements in drainage and garbage removal!
Complete word intelligence in one call. Free tier — 50 lookups/day.