hydrodynamic

HY-dro-dy-NAM-ik /ˌhaɪdroʊdaɪˈnæmɪk/
adjectiveC2GRE
ScientificTechnical

Relating to the forces of fluids on motion, or designed to move through water with the least possible resistance.

Used to describe the shape of boats, swimsuits, or the body position of a swimmer.

The story behind the word. Combining the Greek 'hydro' (water) and 'dynamis' (power), this word literally means the power of water in motion. It became a standard technical term in the 18th century.

Word relationships

  • streamlined: A more common word for shapes that reduce resistance in any fluid, including air.
  • clunky: Informal term for something that is not streamlined and creates resistance.

Commonly confused with

  • aerodynamic: Aerodynamic refers to movement through air; hydrodynamic refers to water.

Word family

  • hydrodynamics (noun): The branch of science dealing with forces in liquids.

Collocations

  • hydrodynamic drag
  • hydrodynamic design
  • hydrodynamic efficiency

Example sentences

  • "The hull of the racing shell was designed to be as hydrodynamic as possible." Engineering report
  • "Swimmers wear caps to create a more hydrodynamic surface and reduce drag." Sports science

Memory hook

'Hydro' is water, 'Dynamic' is movement. Fast water movement! Hydro = Water, Dynamic = Motion.

When not to use

Do not use this for simple floating; it implies movement and the physics of flow.

Fun facts

  • Professional swimmers often shave their body hair to become more hydrodynamic.

Related words

propulsion, resistance

LangBlitz
Take your vocabulary further with LangBlitz

Our English vocabulary app: FSRS spaced repetition, 5,000+ curated words across 119 topic groups, CEFR A1 to C2. Explore your mastery with the beautiful Vocabulary World feature.