ENGLISH
REFERENCE

nautilus

n.
C1 Advanced US //ˈnɔtəɫəs// UK //nˈɔːtɪləs// nau·tilus

n. a large, sea-dwelling animal with a shell that looks like a spiral. It is related to the chambered nautilus and is often called a 'sea horse' in some parts of the world.

n. a marine mollusk of the family Nautilidae, characterized by a chambered, spiral shell. Often referred to as a 'sea horse' in certain regional dialects.


SIMPLE

The nautilus swims slowly through the deep ocean.

CONTEXTUAL

Divers often spot a nautilus near the coral reefs, where it uses its shell to control its buoyancy.

COMPLEX

The nautilus is one of the few living species that has remained largely unchanged for millions of years, making it a living fossil in the world of marine biology.

Synonyms
Origin

From Latin nautilus, from Ancient Greek ναυτίλος (nautílos, “paper nautilus, sailor”).

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