dull as dishwater/ditchwater, extremely dull; boring.
Origin of dishwater
First recorded in 1475–85; dish
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Related Words for dull as dishwatertedious
British Dictionary definitions for dull as dishwater
water in which dishes and kitchen utensils are or have been washed
something resembling thisthat was dishwater, not coffee
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Word Origin and History for dull as dishwater
also dish-water, "water where dishes have been washed," late 15c., from dish (n.) + water (n.). Used figuratively of weak broth, coffee, etc., from 1719.
Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with dull as dishwater
Boring, tedious, as in That lecture was dull as dishwater. The original simile, dull as ditchwater, dating from the 1700s, alluded to the muddy water in roadside ditches. In the first half of the 1900s, perhaps through mispronunciation, it became dishwater, that is, the dingy, grayish water in which dirty dishes had soaked.
The American Heritage® Idioms Dictionary
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