To make someone a bachelor or to cause someone to adopt a bachelor lifestyle; to remain or become unmarried.
From bachelor + -ize (suffix from French -iser and Greek -izein meaning to make or become). The -ize suffix is one of English's most productive verb-creating tools, allowing adjectives and nouns to be converted into action words.
The verb bachelorize is quite rare today, but it shows how English speakers once genuinely thought of bachelorhood as something you could actively become rather than just something that happened to you—it assumes transformation, not passivity.
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