Sentence:  Koetsu learned the technique of <WSD>Raku</WSD> pottery from the <WSD>Raku</WSD> potter Kichizaemon Jokei (1561-1635) and his son Nonko (aka Donyu; 1599-1656), who also had the name Kichibei. 
Meaning of the word marked with <WSD> tags:  A style of Japanese pottery, considered the traditional style for the pottery used in the Japanese tea ceremony; ("especially capitalised") such pottery made by the Raku family.