Definition of "modulate" []

• To adjust or adapt to a certain proportion; regulate or temper. (verb-transitive)
• To change or vary the pitch, intensity, or tone of (one's voice or a musical instrument, for example). (verb-transitive)
• Electronics To vary the frequency, amplitude, phase, or other characteristic of (electromagnetic waves). (verb-transitive)
• Electronics To vary (electron velocity) in an electron beam. (verb-transitive)
• Music To move from one key or tonality to another by means of a melody or chord progression. (verb-intransitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "He often possessed a voice that was a marvelous instrument, a voice he could modulate from a sepulchral whisper to a crashing thunder clap."
• "The idea is to kind of modulate the depth -- to have more gentle moments, then have kind of deeper moments."
• "Without the ability to add additional pressure above this very low maximum, the ability to "modulate" pressure, except towards even less pressure (and lower oxygen dose), does not even exist."