rudder

noun

rud·​der ˈrə-dər 

1

: an underwater blade that is positioned at the stern of a boat or ship and controlled by its helm and that when turned causes the vessel's head to turn in the same direction

2

: a movable auxiliary airfoil on an airplane usually attached at the rear end that serves to control direction of flight in the horizontal plane see airplane illustration

3

: a guiding force or strategy

rudderless

ˈrə-dər-ləs 

adjective

Examples of rudder in a Sentence

Recent Examples on the Web

The program wants to understand how a plane performs without flaps, rudders, ailerons, or other moving surfaces that normally control motion. —Sujita Sinha, Interesting Engineering, 26 Nov. 2025

The goal of the X-65 is to study how to do away with things like rudders, flaps, ailerons and other control surfaces. —New Atlas, 25 Nov. 2025

The Mary’s rudder soon splintered against a rocky bar at the entrance to Natal Bay – what is now Durban, South Africa. —Adam L. Rovner, The Conversation, 31 Oct. 2025

On Saturday, the makeshift vessel of wooden planks on pontoons with a wooden rudder, beached in the choppy surf off the Martin County island, prompting the sheriff’s office to issue a statement on social media. —David Goodhue, Miami Herald, 26 Oct. 2025

Word History

Etymology

Middle English rother, from Old English rōther paddle; akin to Old English rōwan to row

First Known Use

15th century, in the meaning defined at sense 1

Rhymes for rudder

• scudder
• shudder
• udder

Kids Definition

rudder

noun

rud·​der ˈrəd-ər 

: a flat movable piece (as of wood or metal) attached to the rear of a ship or aircraft for steering