Western American English
The west was the last area in the United States to be reached during the gradual westward expansion of English-speaking settlement and its history shows considerable mixing of the linguistic patterns of other regions. As the settlement populations are relatively young when compared with other regions, Western American English is a dialect area in formation.
- baby buggy as opposed to baby carriage (more common east of the Mississippi River, mixed in the region between the Mississippi and Appalachian Mountains, rare east of the Appalachians)
- buckaroo: cowboy. Originating in California, it is an Anglicization of the Mexican vaquero; the corresponding term which originated in Texas is "wrangler" or "horse wrangler", itself an Anglicization of the Mexican caballerango.
- gunnysack as opposed to burlap bag (the latter more common east of the Mississippi)
- hella: adverb; very, adjective; much many
- mud hen: a common term for the American coot
- shivaree as opposed to belling or serenade ("shivaree" is the more common usage east of the Mississippi and in Kentucky and Tennessee; "belling" is the more common usage in Ohio, while "serenade" is the more common usage in Atlantic states—except New York and Connecticut—and the Appalachians)
Phonology and phonetics 
- Unlike the Inland North (or Great Lakes), cot–caught merger and no Northern Cities Shift.
- Unlike the South, no glide deletion of /ai/.
- The Western dialect is not clearly distinct from either Canadian or Midland American English:
- less Canadian raising of the /au/ diphthong than in Canada, but, like Canada, widespread raising of the /ai/ diphthong.
- like in Canada and much of the Midland, /ɑ/ allophones may be either rounded or unrounded due to a lack of phonemic distinction between /ɑ/ and /ɒ/, and these are further back than in the Great Lakes.
- Unlike the Highland South, /ou/ is conservative (little fronting) and the cot–caught merger is complete (except in San Francisco).
- But /u/ is being fronted like in most of North America.
- A minority of speakers have the pin–pen merger.
Local dialects 
- California English
- Utah English
- Wyoming English
- Idaho English
- Hawaiian English
- Pacific Northwest English
- Craig M. Carver, American Regional Dialects: A Word Geography (Ann Arbor: University of Michigan, 1987), pp. 206f
- Carver, American Regional Dialects, p. 223
- Labov, William, Sharon Ash, and Charles Boberg (2006). The Atlas of North American English. Berlin: Mouton de Gruyter. ISBN 3-11-016746-8