Variant of Wilmer, from Germanic 'wil' (will/desire) and 'mari' (famous), meaning 'famous for resolve'.
Wilmur is a variant of Wilmer, from Germanic elements meaning will or desire and famous, yielding the sense of being “famous for resolve.” That combination of determination and renown fits the older Germanic naming pattern very well, since strength of purpose was often prized as much as status.
The name therefore carries a solid, traditional authority. In modern ears, Wilmur feels sturdy, uncommon, and slightly old-fashioned in a respectable way. It has the strength of a surname-adjacent given name and the seriousness of an older European masculine form.
The meaning gives it inner tension in a good way: ambition joined with reputation. Wilmur sounds like a name that would rather endure than trend.