Answer: The closest antonym for the word "customary" is "unusual" or "atypical."
When something is customary, it means it is usual, common, or typical. For example, wearing a uniform to school is customary in some countries.
On the other hand, when something is unusual, it means it is not usual or common. For instance, wearing casual clothes instead of a uniform to school would be considered unusual in a school where uniforms are customary.
Therefore, the closest antonyms for customary are unusual and atypical, as they represent something that deviates from the usual or common practice.
Step-by-step explanation: