kelp

noun

ˈkelp 

plural kelps or kelp

1

a

: any of various large marine brown algae that are large seaweeds (order Laminariales) growing in cool waters

Only canopy-forming kelp are visible on the sea surface.

—Glenn Scherer

Kelps grow fast, drawing on all the minerals and vitamins and nutrients they can from the watershed and the sun.

—Zachariah Bryan

… thickets of kelp forming submarine forests in the bay.

—Jeff Phillips

see also bladder kelp, bull kelp, giant kelp

b

: a mass or growth of large seaweeds

The kelp near the outer islands teems with marine plants and animals in far greater abundance than it does closer to the coast …

—John L. Stein

2

a

: a blade (see blade entry 1 sense 2e) of kelp that is usually dried and used as food (as in sushi or soups)

b

: a dietary supplement containing processed kelp

c

: the ashes of seaweed used formerly especially as a source of iodine

Examples of kelp in a Sentence

Recent Examples on the Web

The mounds of kelp washed ashore Orange County beaches by recent storms is a visual not so common in recent years. —Erika I. Ritchie, Oc Register, 6 June 2025

Using cutting-edge camera technology, the film takes us through coral reefs, kelp forests, and other underwater environments, while also wrestling with what human civilization is doing to this fragile but vital biome. —K. Thor Jensen, PC Magazine, 6 June 2025

Through underwater sequences featuring coral reefs, kelp forests, and the vast ocean life, Attenborough shares why a healthy ocean keeps the entire planet stable and flourishing. —Devonne Goode, Parents, 5 June 2025

Research has found that the median recovery rate of kelp beds near Malibu was a mere 7% in the two years after the 2018 Woolsey fire. —Terry Castleman, Los Angeles Times, 11 Mar. 2025

Word History

Etymology

Middle English culp

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing kelp

• bladder kelp
• bull kelp
• giant bladder kelp
• giant kelp
• kelp bass

Rhymes for kelp

• help
• skelp
• whelp
• yelp

Kids Definition

kelp

noun

ˈkelp 

: any of various large brown seaweeds

also : a mass of these

Medical Definition

kelp

noun

ˈkelp 

1

: any of various large marine brown algae that are large seaweeds (order Laminariales) growing in cool waters

2

a

: a dietary supplement containing processed kelp

b

: the ashes of seaweed used formerly especially as a source of iodine