English▸ noun a wide-mouthed cylindrical container made of glass or pottery and typically having a lid, used especially for storing food:
a large storage jar.
▪ the contents of a jar:
a jar of coffee.
▪ British English informal a glass of beer:
let's have a jar
he jumped at the chance to sink a few jars.
– ORIGIN late 16th century: from French jarre, from Arabic jarra.