1
: habitat or environment
ecospecies
2
: ecological or environmental
ecocatastrophe

Word History

Etymology

Late Latin oeco- household, from Greek oik-, oiko-, from oikos house — more at vicinity

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Cite this Entry

“Eco-.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/eco-. Accessed 3 Feb. 2026.

Kids Definition

eco-

combining form
: habitat or environment
ecosystem
Etymology

Greek oikos "house, household"

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