underside

American  

[uhn-der-sahyd] / ˈʌn dərˌsaɪd /

noun

• undersides
  plural

1. an under or lower side.

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underside British  

/ ˈʌndəˌsaɪd /

noun

1. the bottom or lower surface

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Other Word Forms

Noun Inflected Forms

• undersides
  plural

Etymology

Origin of underside

First recorded in 1670–80; under- + side ¹

Example Sentences

See Examples For:

underside undersides

The snakes are named for their distinctive yellow underside, which contrasts dramatically with their darker top half.

From Los Angeles Times ● Sep. 17, 2026

Scientists discovered that the shape of the underside of the ice shelf strongly affects how seawater circulates below it.

From Science Daily ● May 10, 2026

Serbian midfielder Samardzic held his composure to slam home the penalty left-footed with the ball glancing the underside of the crossbar on its way into the net.

From Barron's ● Feb. 25, 2026

With the game still goalless, Delap pressured Phillips into a mistake as he tried to clear and the ball looped up, struck the underside of the bar and bounced down onto the goalline.

From BBC ● Feb. 13, 2026

I see the smoldering remains of the Justice Building in District 13 and just catch the black-and-white underside of a mockingjay’s wing as it flies across the upper right-hand corner.

From "Catching Fire" by Suzanne Collins

Over two days in July, his team did eight one-hour dives, exploring the undersides of rocky reefs to count the eggs.

From BBC ● Aug. 29, 2026

Aescape has heated “hands,” which look like giant pads with touch points on their undersides.

From Los Angeles Times ● Dec. 3, 2024

Rignot said the project helped him and his colleagues develop a better understanding of the behavior of seawater on undersides of Thwaites Glacier.

From Science Daily ● May 20, 2024

Certain species, like the pythons, have specialized muscles that connect their ribs directly to their skin, allowing them to use just the skin on their undersides to push against the ground and move forward.

From Slate ● Mar. 8, 2024

And he dawdled as the clouds turned their mackerel undersides to him and the cool of the late afternoon started to settle in over the town.

From "Lizzie Bright and the Buckminster Boy" by Gary D. Schmidt