Cornelis Wind (7 November 1867 – 7 August 1911) was a Dutch physicist.

After his appointment in 1905 as a professor at the Utrecht University in mathematical physics and theoretical mechanics, he remained in different positions at the KNMI until his death in 1911.

Wind previously showed the electromagnetic character of X-rays and determined their wavelength by diffraction.

[3] In their Nobel Prize lectures, both Compton and Von Laue referred to the work of Haga and Wind from 1899.

[4] In July 1911, he applied for and resigned as a member of the supervisory committee of the National Institute for the Exploration of the Sea and as a delegate of the Netherlands from the Permanent International Council for the Exploration of the Sea, based in Copenhagen.