from The American Heritage® Dictionary of the English Language, 4th Edition
- A river, about 473 km (294 mi) long, of northwest Oregon flowing generally northward to the Columbia River near Portland. The Willamette Valley, a fertile agricultural region, was first settled in the 1830s by pioneers traveling west along the Oregon Trail.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a river in western Oregon that flows north into the Columbia River near Portland
Sorry, no etymologies found.