How many letters are there in the longest word recognized by the Oxford Dictionary?

The longest word recognized by the Oxford Dictionary is "pneumonoultramicroscopicsilicovolcanoconiosis," which is a term referring to a type of lung disease caused by inhaling very fine silicate or quartz dust. This word contains 45 letters, making it the longest word in the dictionary.

To arrive at this answer, an understanding of both the components of the word and what constitutes a "recognized" term in the Oxford Dictionary is essential. Words like "pneumonoultramicroscopicsilicovolcanoconiosis" are not typically used in common conversation but are examples of technical or medical terminology that the dictionary acknowledges due to their legitimacy and widespread recognition in certain fields. This acknowledgment by the Oxford Dictionary solidifies the word's status as the longest in its record, thus confirming that the correct answer is indeed 45 letters.