To make something less useful or to treat something as if it has no usefulness or value.
From dis- (prefix meaning 'opposite of') + utiliz (from utility) + -e suffix. This rare verb combines the prefix with utility to express the action of removing usefulness.
This is an extremely rare word that you'd almost never encounter in everyday English, but it perfectly demonstrates how the 'dis-' prefix can turn almost any word into its opposite—even needing to create brand new verbs when expressing opposite concepts.
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