water telescope
noun
1 Astronomy a telescope whose tube is filled with water, used especially to investigate aberration of light and the propagation of light in different media (now historical and rare ).
2An instrument used to make observations beneath the surface of water, consisting of a container or tube with a transparent bottom.
Origin
Late 18th century; earliest use found in Philosophical Transactions of the Royal Society of London.
- split
- splitboard
- split-brain
- split decision
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- split hairs
- split-half
- split image
- split infinitive
- split-level
- split one's sides (also split a gut)
- split pea
- split-personality disorder
- split-phase
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- split-rail
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- splitter