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

"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

As if to underline the point, he wore a medallion around his neck featuring NBC’s peacock logo.

From The Wall Street Journal • Feb. 12, 2026

“Recent events, like the appreciation of the euro exchange rate, underline this risk,” he added.

From Barron's • Feb. 4, 2026

While the decision on intervention lies with Japan’s finance ministry, minutes from the BOJ’s meeting last month underline that the central bank is keeping a close eye on the yen.

From The Wall Street Journal • Jan. 28, 2026

But even she insisted, “I want you to underline in red that it was the cherished dream of the girls to liberate the land, but none of us wanted to fight—to kill.”

From "A Thousand Sisters" by Elizabeth Wein

Related Words

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