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nau·ti·lus

(nôtl-əs)

n. pl. nau·ti·lus·es or nau·ti·li (nôtl-ī′)

1. Any of several cephalopod mollusks of the family Nautilidae of the Indian and Pacific Oceans, especially Nautilus pompilius, having numerous slender tentacles and an external coiled pearly shell divided into air-filled chambers. Also called chambered nautilus, pearly nautilus.

2. The paper nautilus.

[Latin, from Greek nautilos, sailor, nautilus, from nautēs, mariner, from naus, ship; see nāu- in the Appendix of Indo-European roots.]

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nautilus

Nautilus pompilius

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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