thumb index


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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Cite this Entry

“Thumb index.” Dictionary, Merriam-Webster, Accessed 28 Feb. 2021.

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More Definitions for thumb index

thumb index


English Language Learners Definition of thumb index

: a series of small cuts in the edge of the pages in a large book that are labeled and that make it easier to open the book to a particular section

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