underline

1 of 2

verb

underlined; underlining; underlines

transitive verb

1
: to mark (something, such as a word) with a line underneath
2
: to put emphasis on : stress
3
: to show clearly or emphatically

underline

2 of 2

noun

un·​der·​line ˈən-dər-ˌlīn How to pronounce underline (audio)
1
: the outline of a quadruped's underbody
also : the ventral surface of a quadruped's body
2
: a horizontal line placed underneath something

Examples of underline in a Sentence

Verb His name was underlined in the book. The accident underlines our need for better safety procedures.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Verb
Russian barrages of missiles and drones – often several hundred in one night – have again underlined its shortfall in air defenses. Tim Lister, CNN Money, 25 Oct. 2025 The research team underlined that their real-world tests are supported by a comprehensive theoretical and computational model, which can accurately predict the complex behavior, of twisting gyroid lattices under different strain rates. Prabhat Ranjan Mishra, Interesting Engineering, 25 Oct. 2025
Noun
As the events of recent days underline, the diplomatic shift is clear. Muhammad Bin Abdulkarim Al-Issa, Time, 10 Oct. 2025 Mitchell and Carter’s absences on Thursday night underline the fragility of the Eagles’ depth on defense. Brooks Kubena, New York Times, 10 Oct. 2025 See All Example Sentences for underline

Word History

First Known Use

Verb

1721, in the meaning defined at sense 1

Noun

1886, in the meaning defined at sense 1

Time Traveler
The first known use of underline was in 1721

Browse Nearby Words

Cite this Entry

“Underline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underline. Accessed 30 Oct. 2025.

Kids Definition

underline

verb
un·​der·​line
ˈən-dər-ˌlīn,
ˌən-dər-ˈlīn
1
: to draw a line under : underscore
2
underline
ˈən-dər-ˌlīn
noun

More from Merriam-Webster on underline

Last Updated: - Updated example sentences
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