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quat·tu·or·de·cil·lion

(kwŏt′-ôr-dĭ-sĭlyən, kwŏt′y-)

1. The cardinal number equal to 10⁴⁵.

2. Chiefly British The cardinal number equal to 10⁸⁴.

[Latin quattuordecim, fourteen (quattuor, four; see k^wetwer- in the Appendix of Indo-European roots + decem, ten; see DECI-) + (M)ILLION.]

quat′tu·or·de·cillion adj.

quat′tu·or·de·cillionth adj.adv. & n.

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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