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definitions

hydroscope

[hahy-druh-skohp]
noun
  1. an optical device for viewing objects below the surface of water.

Origin of hydroscope

First recorded in 1670–80; hydro-1 + -scope
Related formshy·dro·scop·ic [hahy-druh-skop-ik] /ˌhaɪ drəˈskɒp ɪk/, hy·dro·scop·i·cal, adjectivehy·dro·sco·pic·i·ty [hahy-druh-skoh-pis-i-tee] /ˌhaɪ drə skoʊˈpɪs ɪ ti/, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for hydroscopic

hydroscope

noun
  1. any instrument for making observations of underwater objects
Derived Formshydroscopic (ˌhaɪdrəˈskɒpɪk) or hydroscopical, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012