American Heritage® Dictionary of the English Language, Fourth
Edition - n. An act of throwing someone or something out of a
window. Century Dictionary and Cyclopedia - n. The act of
throwing out of the window: as, the defenestration of Prague in
1618, when Bohemian insurgents broke up a meeting of imperial
commissioners and threw two of their number out of the window,
an act which preluded the Thirty Years' war. - n. The act of
throwing something, or someone, out of a window. - n. UK High
profile removal of a person from an organization. - n.
neologism, humorous The act of removing the Microsoft Windows
operating system from a computer in order to install an
alternative one. GNU Webster's 1913 - n. the act of throwing
(something or someone) out of a window. - n. the act of throwing
someone or something out of a window - First attested circa 17th
century, from Latin dē ("from, out") + fenestra ("window"),
historically, it was used as an act of political dissent,
notably the Defenestrations of Prague. (Wiktiona