Customs is the checkpoint at the end of an airport where officers can stop you and open your bags. Two exits, green and red — nothing to declare, something to declare — and a dog working its way along the line of suitcases.
It is also the service itself, the people who tax and control goods coming into a country: a customs officer, a customs declaration, customs duty on a parcel from abroad. The shape is plural but it behaves like a singular — customs was quick this morning. Do not mix it up with custom, which means a tradition: it is the custom here to bring a small gift. Travellers go through customs; a shipment clears customs; and getting stopped at customs is the sentence you hope not to have to say.
1nouncustomsThe place at a border or airport where officials check what travellers are bringing in.
“We were held up at customs for an hour.”
2noungovernmentThe government service that taxes and controls goods entering a country.
“Customs seized the whole shipment at the port.”
Too few real examples of this word to estimate which sense is commonest.
customs is a border control.
Customs is simply the plural of custom. The modern meaning seems to have been pulled into shape by the custom house — Middle English custome hous — until the bare plural could stand for the whole business of the border. The word behind the airport queue is the same one behind local customs and old customs.
Middle English
custome hous
English, today
customs
Plural of custom. Perhaps influenced by or taken as a corruption of custom house, from Middle English custome hous.
Etymology from Wiktionary, CC BY-SA