Dictionary.net

• DOOMSDAY-BOOK, d[=oo]mz'd[=a]-book, n. a book compiled by order of William the Conqueror, containing a survey of all the lands in England, their value, owners, &c.--so called from its authority in judgment (A.S. dóm) on the matters contained in it.

1908 - Chambers's Twentieth Century Dictionary of the English Language
By Thomas Davidson