Umatilla
geographical name
Uma·til·la
ˌyü-mə-ˈti-lə 
river 80 miles (129 kilometers) long in northeastern Oregon flowing west and north into the Columbia River
Cite this Entry
“Umatilla.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Umatilla. Accessed 4 Dec. 2025.
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