krill

American  

[kril] / krɪl /

noun

plural

krill

1. any of the small, pelagic, shrimplike crustaceans of the family Euphausiidae, eaten as food by certain whales.

---

krill British  

/ krɪl /

noun

1. any small shrimplike marine crustacean of the order Euphausiacea : the principal food of whalebone whales

---

krill Scientific  

/ krĭl /

1. Small crustaceans that float in the ocean in huge numbers and are one of the most important parts of zooplankton. Krill are the main food of baleen whales.

---

Etymology

Origin of krill

First recorded in 1905–10, krill is from the Norwegian word kril young fry (of fish)

Explanation

Krill are small crustaceans that resemble shrimp. Hundreds of marine animals rely on krill for food, making them a vital part of the ocean's ecosystem. Krill may be most well-known as the preferred food of baleen whales, which filter the tiny creatures through mouthfuls of sea water. There are actually dozens and dozens of organisms that rely on krill to survive, from birds and fish to penguins, seals, and squid. Krill resemble shrimp, averaging about two inches long. Antarctic krill are one of the world's species with the largest biomass — almost 400 million tons. The Norwegian root, kril, means "small fry of fish."

Example Sentences

But no, Scottish salmon gets its color largely from its diet of shrimp and krill.

From Salon • Feb. 28, 2026

These microscopic plants form the foundation of the food web, feeding krill that sustain penguins, seals, and whales.

From Science Daily • Feb. 28, 2026

The twilight zone teems with life, including krill, squid, fish, octopus, and delicate jelly-like species.

From Science Daily • Nov. 8, 2025

However, their main food source, krill, is threatened by climate change.

From Barron's • Oct. 12, 2025

Many, especially the baleen whales, are placid browsers, straining through vast volumes of ocean for the small animals on which they graze; others eat fish and krill.

From "Cosmos" by Carl Sagan