Added 9 October 2026 basement /ˈbeɪsmənt/ noun Categories: ThingsUncommon Words In Latin: basis Wiktionary noun ! Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about basement at Wordnik → Where our words come from → The lowermost portion of a structure partly or wholly below ground level; often used for storage. The ground floor facade or interior in Renaissance architecture. Related Words: cellardownstairscornerstonekeystonevaultpedestalatriumpillarbunkerclosetlockerexcavation Back to today's word