An earthenware teapot, often used for brewing hojicha or genmaicha. 急須 is more common for everyday green tea.
Etymology
The word 急須 originally referred to a vessel for heating water or sake in China. In Japan, it came to denote a small teapot for brewing tea. The kanji 急 (quick) and 須 (necessary) are ateji, chosen for their sounds rather than their meanings.
