A device used to measure the rise of water in the Nile at the flood(noun)
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Use "nilometer" in a sentence
"It has been taken for a kind of nilometer, for a sculptor's or modeller's stand, or a painter's easel for an altar with four superimposed tables, or a sort of pedestal bearing four door-lintels, for a series of four columns placed one behind another, of which the capitals only are visible, one above the other, etc."
"At this time of year, the nilometer should have been mostly dry, the waters of the Nile receding by October."
"Or we can spend precious hours trying to find and steal a boat and cross a flooding river to the nilometer."