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stim·u·lus

(stĭmyə-ləs)

n. pl. stim·u·li (-lī′)

1. Something causing or regarded as causing a response.

2. An agent, action, or condition that elicits or accelerates a physiological or psychological activity or response.

a. Something that incites or rouses to action; an incentive: "Works which were in themselves poor have often proved a stimulus to the imagination" (W.H. Auden).

b. Government spending designed to generate or increase economic activity.

[Latin, goad.]

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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