coulee

[Alan H. Hartley]

Here's the OED entry:

coulée. Also (U.S.) -ee, -ie, coolie, -ey.
[a. F. coulée flow, f. couler to flow. Sense 2 appears to have arisen
among the French trappers in the Oregon region.]
1. Geol. A stream of lava, whether molten or consolidated into rock; a
lava-flow.
1839 Murchison Silur. Syst. i. xxxii. 428 Large stratiform and
horizontal coulées of volcanic rock.
1879 Rutley Stud. Rocks iv. 32 Molten viscous lava, forming flows or
coulées.
2. In the Western regions of Canada and the United States: A deep ravine
or gulch scooped out by heavy rain or melting snow, but dry in summer.
1807 in Amer. State P., Publ. Lands (1832) I. 313 Bounded in front by
the river Detroit, and in rear by a coulée or small run.
Ibid. 346 Bounded..above by a creek (or coulée) called ventre de bœuf.
1860 in Bartlett Dict. Amer.
1881 Chicago Times 14 May, These ‘coolies’ are dry during the summer
season, but are flooded in the spring of the year.
1881 N.Y. Times 18 Dec. in N. & Q. 6th Ser. V. 65/1 Every ravine short
of an inhabitable valley is called a ‘cooley’.
1884 Lisbon (Dakota) Clipper 13 Mar., She [a cow] was discovered in a
cooley.
1890 Harper’s Mag. Aug. 383/1 Reno came quickly to a shallow ‘cooley’
(frontierism for gully), that led down..to the stream.
----
Contrary to usual OED practice, the earliest-attested sense is not
placed first, probably because the editors believed that sense 1. was
clearly the primary one even though it lacked earlier attestation than
2. I think it's more likely that the two senses developed
(semi-)independently from the root-meaning 'flow'.

Alan