Final answer:
The antonym of 'increase' is 'abate', which means to make something smaller or less.
Step-by-step explanation:
The antonym of the word 'increase' is 'abate'. Increase means to make something larger or more, while abate means to make something smaller or less. For example, if you increase the volume of a song, it becomes louder. On the other hand, if you abate the volume, it becomes softer.
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