Wilsie is an uncommon given name of American origin, derived from the occupational surname Wills, which was originally given to a maker of willow baskets or perhaps a weaver of willow. The name is composed of the Old English elements 'wilig' meaning 'willow' and 'scian' meaning 'basket'. It has been occasionally used as a given name in the United States since the mid-20th century, but it remains quite rare today.
The name Wilsie appears to have been quite popular at the turn of the century, with peaks in popularity between 1899 and 1920. After the 1930s, there was a significant drop-off in its usage, suggesting it may not have been favored as much during the latter half of the century.