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na·ta·to·ri·um

(nā′tə-tôrē-əm, năt′ə-)

An indoor swimming pool.

[Late Latin natātōrium, place for swimming, from neuter of Latin natātōrius, of swimming, from natātus, act of swimming, from past participle of natāre, frequentative of nāre, to swim; see NATATORIAL.]

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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