index case
n.— «A man whom doctors call the “index case”—the first patient they knew about—got sick in December 2006 and was hospitalized at the Mayo Clinic for about two weeks.» —“A Medical Mystery Unfolds in Minnesota” by Denise Grady in Austin, Minnesota New York Times Feb. 5, 2008. (source: Double-Tongued Dictionary)
Further reading
Carrie Ann and her cousin Danielle from Minneapolis, Minnesota, wonder about the pronunciation of the word rhetoric. Is the stress on the first syllable or the second? This is part of a complete episode.
Related
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