Question: Could ancient Americans have expanded the definition of "horse" to include new meanings?

Loan shifting: We must consider the possibility that the ancient author was applying familiar terms to unfamiliar animals that were encountered in the New World

Joseph Smith obviously knew what a "horse" looked like. It stands to reason, therefore, that when Joseph said "horse" that this is exactly what he meant. If we consider, however, that Joseph was receiving revelation that simply conveyed what was written by the ancient author, we must consider the possibility that the ancient author was applying familiar terms to unfamiliar animals that were encountered in the New World. It is important to remember that the Book of Mormon itself is not an ancient text—it is a nineteenth-century translation of an ancient text. Modern readers need to have an understanding of what the ancient author was attempting to convey. Some of the things that seem "plain" to us are not so "plain" upon further investigation or once we understand the culture that produced the text.

For a detailed response, see: Loan shifting: "Horses" as deer and tapirs

See also Neal Rappleye's "Put Away Childish Things: Learning to read the Book of Mormon with Mature Historical Thought" from the 2017 FairMormon Conference. It details other loanshifts.

Europeans coming to the New World were not the only ones who struggled to label new animal species. The introduction of Old World animals into the New World, such as horses and cattle, also created labeling problems for Native Americans and terms for widely different species—such as deer, tapirs, and most commonly dogs—were loanshifted to horses by various native cultures throughout the Americas (see table 2)…

Notes

Question: Could ancient Americans have expanded the definition of "horse" to include new meanings?