dodo - as dead as a dodo

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As dead as a dodo

Meaning: unambiguously and unequivocally dead.

Lewis Carroll used the Dodo as a character in Alice's Adventures in Wonderland, 1865, and it was the popularity of this book that lead to the widespread use of the phrase 'as dead as a dodo'.

There are citings of the phrases 'as rare as the dodo' in the 1860s and in the 1870s we find 'as extinct as a dodo'. The earliest record I can find of 'as dead as a dodo' is a reprint of a story from a Liverpool newspaper in the Bangor Daily Whig And Courier, May 1891:

"After the next general election Mr. Parnell will have only four followers. Except as a private member of Parliament he is as dead as a dodo."