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ca·tal·y·sis

(kə-tălĭ-sĭs)

n. pl. ca·tal·y·ses (-sēz′)

The action of a catalyst, especially an increase in the rate of a chemical reaction.

[Greek katalusis, dissolution, from katalūein, to dissolve : kata-, intensive pref.; see CATA- + lūein, to loosen; see leu- in the Appendix of Indo-European roots.]

cat′a·lytic (kăt′l-ĭtĭk) adj.

cat′a·lyti·cal·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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