kelp

American  

[kelp] / kɛlp /

noun

1. any large, brown, cold-water seaweed of the family Laminariaceae, used as food and in various manufacturing processes.

2. a bed or mass of such seaweeds.

3. the ash of these seaweeds.

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verb (used without object)

1. to burn these seaweeds for their ash.

kelp British  

/ kɛlp /

noun

1. any large brown seaweed, esp any in the order Laminariales

2. the ash of such seaweed, used as a source of iodine and potash

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kelp Scientific  

/ kĕlp /

1. Any of various brown, often very large seaweeds that grow in colder ocean regions. Kelps are varieties of brown algae of the order Laminariales, with some species growing over 61 m (200 ft) long. Kelps are harvested as food (primarily in eastern Asia), as fertilizer, and for their sodium and potassium salts, used in industrial processes. Kelps are also a source of thickening agents and colloid stabilizers used in many commercial products.

2. See more at brown alga

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Etymology

Origin of kelp

1350–1400; apparently dialectal variant of Middle English culp < ?

Explanation

Kelp is a common type of seaweed. You might encounter kelp scuba diving in the ocean, or even while diving into your miso soup. Kelp is a plant that grows in the ocean which you'll often see on the beach at low tide or waving in the water. Many people eat different forms of kelp too — in Japan, two popular edible seaweeds are arame and kombu, both types of kelp that you've probably tasted if you've dined on miso soup. Kelp comes from the Middle English culpe, but its earlier origins are a mystery.

Example Sentences

Others are much larger and multicellular, such as kelp, slime molds, and red algae.

From Science Daily • May 7, 2026

The environmental case for kelp is part of what sustains her.

From BBC • Apr. 29, 2026

The challenge is no longer simply growing kelp, but processing it, distributing it, and building enough demand to sustain farmers at scale.

From BBC • Apr. 29, 2026

It brought major disruption to marine ecosystems: mass die-offs of seabirds, fishery disasters, kelp degradation, whale entanglements, sea lion starvation, fish migration and harmful algal blooms, Amaya said.

From Los Angeles Times • Apr. 16, 2026

Its shell was more like a landmass—hills of bone, shiny pearl valleys, kelp and moss forests, rivers of seawater trickling down the grooves of its carapace.

From "The House of Hades" by Rick Riordan

Related Words

• seaweed