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thumb index

noun
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Definition of thumb index

: a series of usually labeled notches cut in the fore edge of a book (such as a dictionary) to facilitate reference

Examples of thumb index in a Sentence

a dictionary that has a thumb index

First Known Use of thumb index

1903, in the meaning defined above

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Time Traveler for thumb index

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The first known use of thumb index was in 1903

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Dictionary Entries Near thumb index

thumbiest

thumb index

thumb-indexed

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Cite this Entry

“Thumb index.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thumb%20index. Accessed 29 Jun. 2022.

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