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

Part of his work focuses on scaling up kelp harvesting off the Alaskan coast. —Matthew Carey, Deadline, 29 Mar. 2026

Ocean seaweed, or kelp, is also very vulnerable to warm water and invasive species that thrive in those conditions take over. —Laylan Connelly, Oc Register, 27 Mar. 2026

For his curry’s base, Jacobs used green curry paste and kombu, a type of kelp used in Japanese cooking. —Rachel Bernhard, jsonline.com, 16 Mar. 2026

During Ocean Week, each grade level explores a different marine habitat, building ocean literacy across ponds, the seashore, sandy beaches, wetlands, kelp forest and the open ocean. —Karen Billing, San Diego Union-Tribune, 11 Mar. 2026

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