resonance

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The quality or condition of being resonant: words that had resonance throughout his life.
2. n. Richness or significance, especially in evoking an association or strong emotion: "It is home and family that give resonance . . . to life” ( George Gilder). "Israel, gateway to Mecca, is of course a land of religious resonance and geopolitical significance” ( James Wolcott).
3. n. Physics The increase in amplitude of oscillation of an electric or mechanical system exposed to a periodic force whose frequency is equal or very close to the natural undamped frequency of the system.
4. n. Physics A subatomic particle lasting too short a time to be observed directly. The existence of such particles is usually inferred from a peak in the energy distribution of its decay products.
5. n. Acoustics Intensification and prolongation of sound, especially of a musical tone, produced by sympathetic vibration.
6. n. Linguistics Intensification of vocal tones during articulation, as by the air cavities of the mouth and nasal passages.
7. n. Medicine The sound produced by diagnostic percussion of the normal chest.
8. n. Chemistry The property of a compound having simultaneously the characteristics of two or more structural forms that differ only in the distribution of electrons. Such compounds are highly stable and cannot be properly represented by a single structural formula.

Century Dictionary and Cyclopedia

1. n. The act of resounding, or the state or quality of being resonant.
2. n. In acoustics:
3. n. The prolongation or repetition of sound by reflection; reverberation; echo.
4. n. The prolongation or increase of sound by the sympathetic vibration of other bodies than that by which it is originally produced. Such sympathetic vibration is properly in unison either with the fundamental tone or with one of its harmonics. It occurs to some extent in connection with all sound. It is carefully utilized in musical instruments, as by means of the sounding-board of a pianoforte, the body of a violin, or the tube of a horn. In many wind-instruments, like the flute, and the flue-pipes of an organ, the pitch of the tone is almost wholly determined by the shape and size of the resonant cavity or tube. In the voice, the quality of both song and speech and the distinctions between the various articulate sounds are largely governed by the resonance of the cavities of the pharynx, mouth, and nose.
5. n. In medicine, the sound evoked on percussing the chest or other part, or heard on auscultating the chest while the subject of examination speaks either aloud or in a whisper.
6. n. In electricity, the condition of an alternating electric circuit in which the capacity reactance equals or approximately equals the inductive reactance. These two reactances therefore neutralize each other more or less completely, and the current is limited by the resistance only, so that very large values of currents, with correspondingly high voltages, may appear in the circuit. The condition of resonance depends on the frequency of the alternating current; and, inversely, in any circuit containing capacity and self-inductance, a certain frequency exists where resonance occurs.
7. n. In psychology: A term applied, in the James-Lange theory of emotion, to the complex of bodily changes reflexly aroused by the object which excites emotion. “The changes are so indefinitely numerous and subtle that the entire organism may be called a sounding-board.”
8. n. By extension of meaning, the sympathetic arousal in oneself, as if by echo, of a state of feeling whose manifestations one is observing in another, or the course of which one is tracing in imagination, but of which one has had no direct and first-hand experience.

Wiktionary

1. n. The condition of being resonant.
2. n. A resonant sound, echo
3. n. figuratively Something that evokes an association, or a strong emotion.
4. n. physics The increase in the amplitude of an oscillation of a system under the influence of a periodic force whose frequency is close to that of the system's natural frequency.
5. n. nuclear physics A short-lived subatomic particle that cannot be observed directly.
6. n. An increase in the strength or duration of a musical tone produced by sympathetic vibration.
7. n. chemistry The property of a compound that can be visualized as having two structures differing only in the distribution of electrons.

GNU Webster's 1913

1. n. The act of resounding; the quality or state of being resonant.
2. n. (Acoustics) A prolongation or increase of any sound, either by reflection, as in a cavern or apartment the walls of which are not distant enough to return a distinct echo, or by the production of vibrations in other bodies, as a sounding-board, or the bodies of musical instruments.
3. n. (Physics) A phenomenon in which a vibration or other cyclic process (such as tide cycles) of large amplitude is produced by smaller impulses, when the frequency of the external impulses is close to that of the natural cycling frequency of the process in that system.
4. n. (Electronics) An electric phenomenon corresponding to that of acoustic resonance, due to the existance of certain relations of the capacity, inductance, resistance, and frequency of an alternating circuit; the tuning of a radio transmitter or receiver to send or detect waves of specific frequencies depends on this phenomenon.

WordNet 3.0

1. n. having the character of a loud deep sound; the quality of being resonant
2. n. an excited state of a stable particle causing a sharp maximum in the probability of absorption of electromagnetic radiation
3. n. a vibration of large amplitude produced by a relatively small vibration near the same frequency of vibration as the natural frequency of the resonating system
4. n. a relationship of mutual understanding or trust and agreement between people
5. n. the quality imparted to voiced speech sounds by the action of the resonating chambers of the throat and mouth and nasal cavities