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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The first known use of thumb index was in 1903

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Cite this Entry

“Thumb index.” The Dictionary, Merriam-Webster Inc., Accessed 24 January 2020.

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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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Rhyming Dictionary: Words that rhyme with thumb index

Comments on thumb index

What made you want to look up thumb index? Please tell us where you read or heard it (including the quote, if possible).


a feeling of well-being or elation

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