Secchi disc


Sec·​chi disc
: a reflective disc lowered into a body of water to permit measurement of the relative transparency of the water by recording the depth at which the disc is no longer visible

Word History


after Angelo Secchi †1878 Italian astronomer

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Dictionary Entries Near Secchi disc

Cite this Entry

“Secchi disc.” Dictionary, Merriam-Webster, Accessed 8 Dec. 2023.

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