English Reference

Word

keel

US/ˈkiɫ/

UK/kˈiːl/

Definition

n. the long piece of wood or metal along the bottom of a boat that helps it stay stable and straight in the water.

n. the longitudinal structural member along the base of a ship's hull, providing stability and structural integrity. In botany, refers to the two lowest petals of a pea flower that are joined together.

Examples

“The ship's keel hit a rock in the shallow water.”

“The shipwright inspected the keel for damage before the vessel was cleared for its maiden voyage across the Atlantic.”

“By lowering the heavy keel, the designers ensured the yacht would remain upright even when subjected to the forceful lateral pressures of a gale-force wind.”

Examples

simple

“The ship's keel hit a rock in the shallow water.”

contextual

“The shipwright inspected the keel for damage before the vessel was cleared for its maiden voyage across the Atlantic.”

complex

“By lowering the heavy keel, the designers ensured the yacht would remain upright even when subjected to the forceful lateral pressures of a gale-force wind.”

Usage

Often used in the idiom 'on an even keel' to describe a stable or calm situation.

Real-World Examples

“Thanks to the high-quality preservation, the fossil was found to contain subtle ridges, known as "keels," along each of its branches—a feature that had not been detected in other, flatter fossils.”
Phys.org · 9 Sept 2026
“In Britain, where nurses keel over with heat exhaustion, it can feel, at times, as if the single adequately air-conditioned space is the Apple Store; only the iPhones stay cool.”
The Guardian · 14 Aug 2026

Idioms

even keel — Of an emotion or state of mind, the state or characteristic of being under control and balanced.

keel over — To collapse in a faint; to black out, to swoon.

Domains

BotanyNauticalZoology

This entry

Level
C2 · Proficiency
Frequency
Occasional
Updated

Scan code

englishreference.com/q/keel

English Reference