Earth Day

noun

Definition of Earth Day

: a day in April designated for promoting concern for the environment

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First Known Use of Earth Day

1970, in the meaning defined above

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The first known use of Earth Day was in 1970

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Cite this Entry

“Earth Day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Earth%20Day. Accessed 7 Mar. 2021.

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