[seysh] 
| an occasional and sudden oscillation of the water of a lake, bay, estuary, etc., producing fluctuations in the water level and caused by wind, earthquakes, changes in barometric pressure, etc. |
| seiche (sāsh, sēch) n. A wave that oscillates in lakes, bays, or gulfs from a few minutes to a few hours as a result of seismic or atmospheric disturbances. [French dialectal, exposed lake bottom, probably from French sèche, feminine of sec, dry; see sec1.] |
| seiche (sāsh, sēch) Pronunciation Key
An oscillating wave in an enclosed body of water. A seiche may have a period from a few minutes to a few hours and is usually a result of seismic or atmospheric disturbances. |
seiche
rhythmic oscillation of water in a lake or a partially enclosed coastal inlet, such as a bay, gulf, or harbour. A seiche may last from a few minutes to several hours or for as long as two days. The phenomenon was first observed and studied in Lake Geneva (Lac Leman), Switzerland, in the 18th century.
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