Creek bed and Dry wash

Creek bed noun - A channel occupied (or formerly occupied) by a stream.

Dry wash and creek bed are semantically related. In some cases you can replace phrase "Dry wash" with "Creek bed", this phrases are similar.

Dry wash noun - The dry bed of an intermittent stream (as at the bottom of a canyon).

Creek bed and dry wash are semantically related. You can use "Creek bed" instead a noun phrase "Dry wash".