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rap·id

(răpĭd)

adj. rap·id·er, rap·id·est

Moving, acting, or occurring with great speed. See Synonyms at fast¹.

n. often rapids

An extremely fast-moving part of a river, caused by a steep descent in the riverbed.

[Latin rapidus, from rapere, to seize; see rep- in the Appendix of Indo-European roots.]

ra·pidi·ty (rə-pĭdĭ-tē), rapid·ness (răpĭd-nĕs) n.

rapid·ly adv.

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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