giant kelp

noun

plural giant kelps

: a very large, fast-growing brown alga (Macrocystis pyrifera) of cool oceans that often grows in dense patches, may reach a length of 150 feet (45 meters), and has long stipes from which arise leaflike blades with gas-filled air bladders at their base

… giant kelp, the majestic floating seaweed species common to Monterey Bay …

—Peter Fimrite

Gliding through the frigid waters, I marveled at how the light filtered down through the healthy forests of giant kelp—a humongous species of brown algae …

—Ashley Harrell

Giant kelps bent to the seafloor from the weight of the mussels growing on them.

—Enric Sala

called also bladder kelp, giant bladder kelp

Examples of giant kelp in a Sentence

Recent Examples on the Web

The reef is essentially an anchor for giant kelp, which grows tall and thick to create the forests of the sea. —Phil Diehl, San Diego Union-Tribune, 23 Mar. 2024

Under ideal conditions, one species of seaweed, giant kelp, can elongate by around two feet per day. —Saima May Sidik, Smithsonian Magazine, 22 Jan. 2024

Down here, forests are made of giant kelp, which is a perennial species, versus bull kelp in Northern California, which is an annual species. —Lisa Deaderick, San Diego Union-Tribune, 21 Jan. 2024

Stretching 150 miles along the Southern California coast, the islands are surrounded by deep submarine canyons, productive giant kelp forests on rocky reefs, and sandy beaches. —Ryan Fonseca, Los Angeles Times, 24 Apr. 2023

Warming seas are making giant kelp less nutritious, and replacing the consumption of beef and poultry with tropical forest bushmeat would significantly reduce greenhouse gas emissions. —Matthew Gavin Frank, Harper's Magazine, 21 Jan. 2022

The two-story giant kelp forest mirrors many of the kelp forests divers encounter in the waters off San Diego: In this exhibit, visitors can spot leopard sharks, moray eels and more. —Los Angeles Times, 20 Jan. 2022

Since February, researchers have also sought to capture carbon by cultivating giant kelp off the coast of Namibia—in effect creating a carbon-hungry submarine forest. —Bypaul Voosen, science.org, 16 Dec. 2022

Word History

First Known Use

1871, in the meaning defined above