custom

American  

[kuhs-tuhm] / ˈkʌs təm /

noun

1. a habitual practice; the usual way of acting in given circumstances.

2. habits or usages collectively; convention.

3. a practice so long established that it has the force of law.

4. such practices collectively.

5. Sociology. a group pattern of habitual activity usually transmitted from one generation to another.

6. toll; duty.

7. customs,

   1. (used with a singular or plural verb) duties imposed by law on imported or, less commonly, exported goods.

   2. (used with a singular verb) the government department that collects these duties.

   3. (used with a singular verb) the section of an airport, station, etc., where baggage is checked for contraband and for goods subject to duty.

8. regular patronage of a particular shop, restaurant, etc.

9. the customers or patrons of a business firm, collectively.

10. the aggregate of customers.

11. (in medieval Europe) a customary tax, tribute, or service owed by peasants to their lord.

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adjective

1. made specially for individual customers.

   custom shoes.

2. dealing in things so made, or doing work to order.

   a custom tailor.

custom British  

/ ˈkʌstəm /

noun

1. a usual or habitual practice; typical mode of behaviour

2. the long-established habits or traditions of a society collectively; convention

   custom dictates good manners

3. 1. a practice which by long-established usage has come to have the force of law

   2. such practices collectively (esp in the phrase custom and practice )

4. habitual patronage, esp of a shop or business

5. the customers of a shop or business collectively

6. (in feudal Europe) a tribute paid by a vassal to his lord

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adjective

1. made to the specifications of an individual customer (often in the combinations custom-built , custom-made )

2. specializing in goods so made

Usage

What does custom mean? As a noun, custom means a longstanding practice of a person (such as a daily habit) or a group (such as a cultural practice). As an adjective, custom describes something made to unique specifications, especially something one of a kind. Its synonym is custom-made. The word customs with an s refers to fees paid on imported goods, or the government department that handles such things. It is also the name of the checkpoint in the airport where incoming luggage and goods are inspected for prohibited items. Example: When I travel abroad, it’s my custom to bring home a custom-made souvenir that highlights the artistic customs of the people who live in that place. The items are usually very unique, which often leads to a lot of questions when I go through customs at the airport!

Related Words

Custom, habit, practice mean an established way of doing things. Custom, applied to a community or to an individual, implies a more or less permanent continuance of a social usage: It is the custom to give gifts at Christmas time. Habit, applied particularly to an individual, implies such repetition of the same action as to develop a natural, spontaneous, or rooted tendency or inclination to perform it: to make a habit of reading the newspapers. Practice applies to a set of fixed habits or an ordered procedure in conducting activities: It is his practice to verify all statements.

Etymology

Origin of custom

First recorded in 1150–1200; Middle English custume, from Anglo-French; Old French costume, from Vulgar Latin co(n)s(uē)tūmin- (unrecorded), replacing Latin consuētūdin-, stem of consuētūdō “habit, practice, tradition,” from consuē(tus) “accustomed” (past participle of consuēscere “to accustom onself,” from con- con- + suēscere “to become accustomed,” akin to suus “one's own”) + -tūdō -tude; cf. costume

Explanation

If something has been done a certain way for a long time and has become generally accepted, it's a custom. Asking strangers for candy on one night a year would seem strange if it weren't an established custom. If you have been imprisoned in a far off country when you were just trying to blend in, you might have misunderstood the local customs. Custom can be traced back to the Latin verb consuescere, meaning "to accustom," in other words "to get used to." Custom can also describe something that you order made just the way you want it. Your five-seated bicycle is very original; was it custom-made?

Example Sentences

Amazon CEO Andy Jassy said: “Our custom AI silicon offers high performance at significantly lower cost for customers, which is why it’s in such hot demand.”

From Barron's • Apr. 20, 2026

Launched in late 2024, it is used by 23,000 customers out of the total base of 150,000 to build custom autonomous agents for use in workflows.

From The Wall Street Journal • Apr. 20, 2026

The expanded agreement includes Amazon’s custom AI chips, 5 gigawatts capacity, and international inference expansion in Asia and Europe.

From Barron's • Apr. 20, 2026

Its custom chips business also has an annual revenue run rate of more than $20 billion, he said.

From MarketWatch • Apr. 20, 2026

We all called her Mother, another Sudanese custom.

From "Lost Boy, Lost Girl" by John Bul Dau

Related Words

• method
• policy
• practice
• rite
• rule
• style
• system