underline

American  

[uhn-der-lahyn, uhn-der-lahyn, uhn-der-lahyn] / ˈʌn dərˌlaɪn, ˌʌn dərˈlaɪn, ˈʌn dərˌlaɪn /

verb (used with object)

underlined, underlining

1. to mark with a line or lines underneath; underscore.

2. to indicate the importance of; emphasize, as by stressing or italicizing.

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noun

1. Printing. a caption under an illustration.

2. a line drawn under something; an underscore.

underline British  

verb

1. to put a line under

2. to state forcibly; emphasize or reinforce

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noun

1. a line underneath, esp under written matter

Other Word Forms

• underlineation noun
• underliner noun
• underlining noun

Etymology

Origin of underline

First recorded in 1715–25; under- + line ¹

Example Sentences

Josh Bivens, the chief economist at the Economic Policy Institute, pointed to Federal Reserve data to underline the discrepancy between the tariffs Americans have paid versus the refunds they are seeing this year.

From Salon • Apr. 15, 2026

For the time being, there are more achievable goals that would serve to underline McIlroy's greatness.

From BBC • Apr. 13, 2026

At early Coachella rehearsals, you could see a well-seasoned group working to underline its distinct cultural voice, while still delivering the exuberant pop it’s beloved for.

From Los Angeles Times • Apr. 9, 2026

"These findings underline the importance of international trade, storage, and flexible policies. Because droughts do not hit all regions at the same time, smart planning can use this natural diversity to buffer global food supplies."

From Science Daily • Mar. 5, 2026

I carefully write in Sundays date and underline it three times.

From "Saints and Misfits" by S.K. Ali

Related Words

• accentuate
• highlight
• indicate
• point up
• stress
• underscore