1
- a traditional and widely accepted way of behaving or doing something that is specific to a particular society, place, or time风俗; 习俗：
the old English custom of dancing round the maypole
围着五朔节花柱跳舞的英格兰老习俗
mass noun custom demanded that a person should have gifts for the child.习俗要求给孩子礼物。
1.1
- in sing. a thing that one does habitually习惯：
it is our custom to visit the Lake District in October.
10月探访湖区是我们的习惯。
1.2
- Law established usage having the force of law or right【律】惯例, 习惯法。
2
- mass noun chiefly Brit. regular dealings with a shop or business by customers〈主英〉（顾客经常性的）光顾, 惠顾：
if you keep me waiting, I will take my custom elsewhere.
你让我久等的话, 我今后就光顾别处去了。
词源
Middle English: from Old French coustume, based on Latin consuetudo, from consuetus, past participle of consuescere 'accustom', from con- (expressing intensive force) + suescere 'become accustomed'.