In the manner of a bachelor; according to bachelor fashion or custom; as bachelors do.
From bachelor + -wise (Old English suffix meaning in the manner or direction of, related to 'way'). The -wise suffix survives in modern words like clockwise and likewise, meaning in that direction or manner.
Bachelorwise is a beautiful example of how archaic -wise combined with occupation words to create vivid adverbs—people said bachelorwise, merchantwise, and priestwise to paint pictures of how different social groups lived, which made English sound almost like different languages for different communities.
Rare -wise suffix form carries gendered assumptions; 'bachelorwise' frames unmarried male comportment as a knowable, describable mode, while no parallel female equivalent carried equal prestige.
Avoid entirely; use 'in unmarried fashion', 'as an unmarried person', or specify the actual comportment.
["in unmarried fashion","as an independent person"]
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