Added 10 October 2026 niceness /ˈnaɪsnɪs/ noun Categories: Describing WordsRare Words noun ! Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about niceness at Wordnik → Where our words come from → A courteous manner that respects accepted social usage. The quality of nice. The quality of being difficult to detect or analyze. you had to admire the subtlety of the distinctions he drew Related Words: subtletypolitenesscongenialitynicerynicelingnice-nellyismfinerykindlinessjollinessdulcenesswhimsicalnessfrolicsomeness Back to today's word