Zuni, or Ashiwi, is a language isolate spoken by over 4500 people in New Mexico and much smaller numbers in parts of Arizona. It is now generally considered a language isolate. The Encyclopedia Britannica categorizes it as a Penutian language, and Bertha Dutton   once posed the hypothetical that according to the Swadesh list, "If the Zuni language is a member of the Penutian language family, then it is a distant relative of the Tanoan languages (Tewi)."  The Penutian Hypothesis  was advanced by Alfred Kroeber and Roland B. Dixon   and later refined by Edward Sapir, and was an attempt to reduce the number of unrelated language families in a culturally diverse area that was centered in California central coast.  While this theory was plausible for some of
the languages, the problem of verification of this theory was that to find any evidence of any cognates between the California languages and Zuni, one would possibly have to trace the languages' lineage by as much as 3000–5000 years or more.

A bibliography of books and articles concerning the Zuni language lists items dealing with syntax and semantics, as does Zuni
Curtis D. Cook's article and the work of Stanley Newman. Others, such as Ruth Bunzel's Pueblo Pottery and Jane M. Young's  book on Rock Art, are important in the study of pragmatics and the Zuni World View  as it is reflected in the Zuni language. The Zuni worldview may properly be considered as a study in orthology.
The form and function of design images and pictographic rock art images and their interpretation according to Zuni mythology
or cosmology sufficed as a form of communication prior to the appearance of a written language.

The Zuni Enigma, by Nancy Yaw Davis  offers a comparative of cognates between the Zuni language and
another language isolate; the Japanese language.  While speculative, it demonstrates a likeness between the Zuni and Japanese languages that is more compelling than that of the Penutian Hypothesis.  Dell Hymes offers information on California languages where one can form a comparative of certain Zuni words to the languages of California, e.g.Wintu, Maidu, Miwok, and may have relevance to studies of the Pueblo Peoples, the Pecos Classification, and the Hohokam.  Also important are the books on and by Frank Hamilton Cushing. He was the first anthropologist to undertake studies by means of the method of Participant observation, and became a member of the Zuni's Priesthood of the Bow during his tenure at the Pueblo from 1879-1884. Of special interest in regard to the Zuni language is his correspondences edited by Jesse Green, and their relevance to the Zuni language as it reflects their world view.

Bibliography for the Zuni Language
Bunzel, Ruth L. The Pueblo Potter: A Study of Creative Imagination in Primitive Art. New York: Dover, 1929.
Bunzel, Ruth L.  Introduction to Zuni Ceremonialism. Introduction by Nancy Pareto.  University of New Mexico Press, 1992.
Bunzel, Ruth L. Zuni Texts. Publications of the American Ethnological Society, 15. New York: G.E. Steckert & Co., 1933.
Cook, Curtis D. "Nucleus and Margin of Zuni Clause Types." Linguistics. 13: 5-37, 1975.
Davis, Nancy Yaw. The Zuni Enigma. Norton, 2000.
Dutton, Bertha P.  American Indians of the Southwest.  Albuquerque: University of New Mexico Press, 1983.
Green, Jesse, ed.  Zuni: Selected Writings of Frank Hamilton Cushing.  Lincoln and London: University of Nebraska Press, 1979.
Green, Jesse. Cushing at Zuni: The Correspondence and Journals of Frank Hamilton Cushing, 1879-1884.  Albuquerque: University of New Mexico Press, 1990.
Hickerson, Nancy P.  "Two Studies of Color: Implications for Cross-Cultural Comparability of Semantic Categories".  In Linguistics and Anthropology: In honor of C.F. Voegelin. pp. 317–330. Ed. By M. Dale Kinkade, Kenneth Hale, and Oswald Werner.  The Peter De Ridder Press, 1975.
Hieb, Louis A. "Meaning and Mismeaning: Toward an Understanding of the Ritual Clowns".  New Perspectives on the Pueblos.  Ed. by Alfonso Ortiz.  pp. 163–195.  Albuquerque: University of New Mexico Press, 1972.
Hymes, Dell H. "Some Penutian Elements and the Penutian Hypothesis".  Southwestern Journal of Anthropology.  13:69-87, 1957.
Miner, Kenneth L. "Noun Stripping and Loose Incorporation in Zuni".  International Journal of American Linguistics. 52: 242-254, 1986.
Newman, Stanley. "Vocabulary Levels: Zuni Sacred and Slang Usage." Southwestern Journal of Anthropology. 11: 345-354, 1955.
Newman, Stanley. Zuni Dictionary. Indiana University Research Center Publication Six. Bloomington: Indiana University, 1958.
Newman, Stanley. "The Zuni Verb 'To Be'".  Foundations of Language, Supplemental Series. Vol.1. Ed. by John W. Verhaar, The Humanities Press, 1967.
Stout, Carol.  "Problems of a Chomskyan Analysis of Zuni Transitivity". International Journal of American Linguistics. 39: 207-223, 1973.
Walker, Willard.  "Inflection and Taxonomic Structure in Zuni".  International Journal of American Linguistics. 32(3): 217-227, 1966.
Walker Willard. "Toward a Sound Pattern of the Zuni".  International Journal of American Linguistics. 38(4):240-259, 1968.
Young, M. Jane. Signs from the Ancestors:Zuni Cultural Symbolism and Perceptions in Rock Art.  Albuquerque: University of New Mexico Press, 1988.

Other websites
Zuni World View "Linguistic and Ontological Implications of the Conceptual Presuppositions of the Zuni Worldview"

Isolated languages