QUIDDITY Meaning of QUIDDITY in English [ 'kwɪdɪti ]■ noun ( plural quiddities ) chiefly Philosophy the inherent nature or essence of a person or thing.OriginME: from med. L. quidditas , from L. quid 'what'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004