Willis may refer to:
Ulmus 'Willis' is a hybrid elm cultivar which originated as a crossing made by a Mr Minnick of Kansas and treated simply as a hybrid. Almost certainly derived from a crossing of the Siberian Elm Ulmus pumila (female parent) and the Red Elm Ulmus rubra, it was originally believed that the male parent was the American Elm Ulmus americana.
'Willis' was described as having a smooth grey bark, large leaves similar to U. americana, and capable of very rapid growth.
'Willis' has not been widely tested for resistance to Dutch elm disease.
First marketed by the Willis Nursery Co., Ottawa, Kansas, circa 1959, it is not known whether the cultivar remains in cultivation in the USA, nor whether it was ever introduced to Europe or Australasia.
Willis, a variant of the name William, is a surname, of Scottish and English origin meaning (Son of William). Notable persons with that surname include:
Child star on the boiling point,
now we'll see if the audience laughs,
Willis on the warpath,
time now for revenge,
Willis he is packin',
he'll get five to ten,
Arnold and Kimberly watchin' Willis' back,
different strokes posse rolling through the hood,