annotation

American  

[an-uh-tey-shuhn] / ˌæn əˈteɪ ʃən /

noun

1. a critical or explanatory note or body of notes added to a text.

2. the act of annotating.

3. note. annot.

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annotation British  

/ ˌænə-, ˌænəʊˈteɪʃən /

noun

1. the act of annotating

2. a note added in explanation, etc, esp of some literary work

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Usage

What does annotation mean? An annotation is a note or comment added to a text to provide explanation or criticism about a particular part of it. Annotation can also refer to the act of annotating—adding annotations. Annotations are often added to scholarly articles or to literary works that are being analyzed. But the term can be used in a more general way to refer to a note added to any text. For example, a note that you scribble in the margin of your textbook is an annotation, as is an explanatory comment that you add to a list of tasks at work. Something that has had such notes added to it can be described as annotated. The word annotation is sometimes abbreviated as annot. (which can also mean annotated or annotator). Example: The annotations in this edition of the book really helped me to understand the historical context and the meanings of some obscure words.

Other Word Forms

• reannotation
  noun

Etymology

Origin of annotation

First recorded in 1425–75, annotation is from the Latin word annotātiōn- (stem of annotātiō ). See annotate, -ion

Explanation

Annotations are simply notes or comments. If you have trouble understanding Shakespeare, you may want to buy a copy of "Hamlet" with annotations on each page that explain all the vocabulary words and major themes. The word annotation comes from the Latin root words ad, meaning "to," and notare, meaning "to note." The act of adding explanatory notes to something is also called annotation, as in "Your friends might be amused by your annotation of the text, but I don't think the professor will accept "No one knows and no one cares!" as a reason for why the protagonist acted the way he did."

Example Sentences

Wang formerly served as CEO of Scale AI, a privately held start-up that started as a data labeling and annotation service.

From Barron's • Apr. 8, 2026

Elon Musk’s artificial intelligence startup xAI has laid off 500 workers from its data annotation team, which helps train its Grok chatbot.

From Los Angeles Times • Sep. 15, 2025

It includes Nat Friedman, former boss of software development platform GitHub, Alexandr Wang of data annotation firm Scale AI and co-creators of OpenAI's models.

From BBC • Jul. 1, 2025

In our proof of concept, we trained neural networks on previously annotated viral protein sequences in pre-trained protein language models and then used them to predict the annotation of new viral protein sequences.

From Salon • May 17, 2024

Scrolling further down the screen, Charles came across a rather unusual annotation: “You didn’t really think we’d make it that easy, did you?”

From "Escape from Mr. Lemoncello's Library" by Chris Grabenstein

Related Words

• glossary