The term 'Sash at a Japanese Tea Ceremony' can be summarized as a traditional sash worn by the host of a Japanese tea ceremony. The sash, known as an OBI, is typically made of silk and is tied around the waist of the host. It is usually brightly colored and decorated with intricate patterns. The OBI is an important part of the tea ceremony, as it symbolizes the host's hospitality and respect for their guests.