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

Cook for 6 minutes, undisturbed, or until browned on the undersides and beginning to firm, then flip with a spatula. — ABC News, 19 Sep. 2026

Two people were injured when a semi-trailer truck hauling steel beams hit the underside of the Lake Avenue bridge over the Edens Expressway near Wilmette on Thursday evening. — Todd Feurer, CBS News, 18 Sep. 2026

The snakes are named for their distinctive yellow underside, which contrasts dramatically with their darker top half. — Fedor Zarkhin, Los Angeles Times, 17 Sep. 2026

Engineers who separately examined the building’s exterior supposedly found widespread corrosion in structural components of the soffit panels along the underside of an overhang that wraps around the center. — Francesca Aton, ARTnews.com, 14 Sep. 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