noun
thermal container; thermos; rice warmer
Refers to insulated containers for keeping food or drink warm, including wide-mouthed thermoses and electric rice warmers. Often seen in compounds like 電子ジャー.
See also: 電子ジャー
お弁当は保温ジャーに入れて持っていく。
I put my lunch in a thermal container and take it with me.
ご飯が冷めないように電子ジャーで保温する。
I keep the rice warm in an electric rice warmer so it doesn't get cold.
noun
General term for a jar, often a glass or plastic container with a lid. Less common than sense 1 in everyday Japanese; 瓶 (びん) is more typical for small jars.
クッキーをジャーに入れて保存する。
I store cookies in a jar.