Final answer:
The literary term in the sentence is 'allusion'. This term refers to a reference to a person, place, event, or literary work that the author expects the reader to understand. The 'Emersonian high' in the given sentence refers to Ralph Waldo Emerson and his set of beliefs, conveying the character's state of mind.
Step-by-step explanation:
The literary term in the sentence "After piloting it west out of Atlanta, he'd arrived in Lake Mead National Recreation Area on July 6, riding a giddy Emersonian high," is termed allusion. An allusion is a figure of speech where the author refers to a subject matter such as a person, place, event, or literary work in a passing reference. In this sentence, the reference to a giddy Emersonian high is an allusion to the philosopher Ralph Waldo Emerson, known for his ideas about Transcendentalism and experiencing heightened states of emotion and inspiration. In this case, the author uses an allusion to Ralph Waldo Emerson, a significant figure in literature, whose philosophy might have influenced the joyful and inspired state of mind of the character in the story.
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