[thuhn-der] 
| 1. | a loud, explosive, resounding noise produced by the explosive expansion of air heated by a lightning discharge. |
| 2. | any loud, resounding noise: the thunder of applause. |
| 3. | a threatening or startling utterance, denunciation, or the like. |
| 4. | to give forth thunder (often used impersonally with it as the subject): It thundered last night. |
| 5. | to make a loud, resounding noise like thunder: The artillery thundered in the hills. |
| 6. | to utter loud or vehement denunciations, threats, or the like. |
| 7. | to speak in a very loud tone. |
| 8. | to move or go with a loud noise or violent action: The train thundered through the village. |
| 9. | to strike, drive, inflict, give forth, etc., with loud noise or violent action. |
| 10. | steal someone's thunder,
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| thun·der (thŭn'dər) n.
v. intr.
To express violently, commandingly, or angrily; roar. [Middle English, from Old English thunor; see (s)tenə- in Indo-European roots.] thun'der·er n. |
The noise created when air rushes back into a region from which it has been expelled by the passage of lightning.
Thunder
often referred to in Scripture (Job 40:9; Ps. 77:18; 104:7). James and John were called by our Lord "sons of thunder" (Mark 3:17). In Job 39:19, instead of "thunder," as in the Authorized Version, the Revised Version translates (ra'amah) by "quivering main" (marg., "shaking"). Thunder accompanied the giving of the law at Sinai (Ex. 19:16). It was regarded as the voice of God (Job 37:2; Ps. 18:13; 81:7; comp. John 12:29). In answer to Samuel's prayer (1 Sam. 12:17, 18), God sent thunder, and "all the people greatly feared," for at such a season (the wheat-harvest) thunder and rain were almost unknown in Palestine.
thunder
sound caused by a lightning discharge. Lightning heats the air in its path and causes a large over-pressure of the air within its channel. The channel expands supersonically into the surrounding air as a shock wave and creates an acoustic signal that is heard as thunder. The loudest thunder heard after a flash to the ground is actually produced by the return stroke that follows the path forged by the initial stroke, or stepped leader. The return stroke is louder because it contains a larger and faster-rising electric current than either the leader or a discharge within a cloud. Because the path of a lightning channel is usually branched, tortuous, and very long, sound waves from more distant portions arrive later than those from nearer portions, accounting for the duration of thunder and for the characteristic claps and rumbles. The distance to a flash can be estimated by measuring the time delay between the flash of light and the thunder-the formula being about three seconds for each kilometre (or five seconds for each mile). Thunder is seldom heard at distances greater than about 20 km (12 miles). See also thunderstorm.
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