v. mod·u·lat·ed, mod·u·lat·ing, mod·u·lates
1. To regulate or adjust to a certain degree: physiological mechanisms that modulate the body's metabolic rate.
2. To change or vary the pitch, intensity, or tone of (one's voice or a musical instrument, for example).
3. Physics To vary the frequency, amplitude, phase, or other characteristic of (a wave, beam, or signal).
4. Biochemistry To act on (a receptor, for example) as an activator, an inhibitor, or both.
To move from one key or tonality to another by means of a melody or chord progression.
[Latin modulārī, modulāt-, to measure off, to regulate, from modulus, diminutive of modus, measure; see med- in the Appendix of Indo-European roots.]
modu·la′tive, modu·la·to′ry (-lə-tôr′ē) adj.
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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:
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