underside

noun

un·​der·​side ˈən-dər-ˌsīd 

ˌən-dər-ˈsīd

1

: the side or surface lying underneath

2

: a side usually hidden from sight

specifically : the more unpleasant or reprehensible side

the underside of politics

Synonyms of underside

• bottom

Examples of underside in a Sentence

the underside of the table

The book explores the underside of human nature.

Recent Examples on the Web

Greenling said some of the sharks had red markings on their undersides, prompting concerns about what the deaths could mean for the water. — Ross Dimattei, CBS News, 12 Aug. 2026

At the same time, the bull directs a spray of urine onto the underside of his neck and then rolls about in the wallow after it is dug, continuing to urinate in the wallow. — Alex Robinson, Outdoor Life, 12 Aug. 2026

Holden eagerly rebels against Pencey Prep, gets the boot, and flees to New York City, a place with its own vices and hazards, but without the sort of propaganda and pretense that obscure the school’s dark underside. — Literary Hub, 10 Aug. 2026

The underside of the top was a bright red which aligned with her shoes. — Jaden Thompson, Footwear News, 10 Aug. 2026

Word History

First Known Use

1660, in the meaning defined at sense 1

Rhymes for underside

• actinide
• aldehyde
• alkoxide
• alongside
• amplified
• arsenide
• beautified
• biocide
• bisulphide
• butoxide
• calcified
• ceramide

Kids Definition

underside

noun

un·​der·​side ˈən-dər-ˌsīd 

ˌən-dər-ˈsīd

: the side or part lying underneath