Cambridge Advanced learner’s Dicionaray 3rd Edition
Tradition is a belief, principle or way of acting which people in a particular society or group have continued to follow for a long time, or all of these beliefs, etc. in a particular society or group
Fireworks have long been an American tradition on the Fourth of July.
Switzerland has a long tradition of neutrality.
[ + that ] There's a tradition in our office that when it's somebody's birthday, they bring in a cake for us all to share.
We decided to break with tradition (= not behave as usual) this year and go away for Christmas.
According to tradition, a headless ghost walks through the corridors of the house at night.
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Custom [ C or U ] a way of behaving or a belief which has been established for a long time
a local/ancient custom
[ + to infinitive ] In my country, it's the custom ( for women) to get married in white. Mr. Yasser Anwar