caster sugar
noun /ˈkɑːstə ʃʊɡə(r)/
/ˈkæstər ʃʊɡər/
(also castor sugar)
[uncountable] (British English)- white sugar in the form of very fine grains, used in cooking
compare granulated sugar幼砂糖 词源mid 19th cent.: so named because it was suitable for use in a castor, a small container with holes in the top, used for sprinkling sugar.