The definition of a typhoon is a tropical cyclone with winds faster than 74 miles per hour that occurs in the North Atlantic Ocean, the Northeast Pacific Ocean east of the dateline, the South Pacific east of 160E and the Northwest Pacific Ocean west of the date line.
An example of a typhoon was Typhoon Songda which reached the Northern Mariana Islands and Japan in 2004 with winds up to 145 miles per hour.
See typhoon in Webster's New World College Dictionary
Origin: < Chin dial. tai-fung, lit., great wind (or < ? Tai, Formosa: hence, Formosa wind); merged with earlier tuphan, tufan < Port tufão < Ar tūfān < Gr typhōn, hurricane, akin to typhos: see typhus
See typhoon in American Heritage Dictionary 4
Origin: Greek tuphōn, whirlwind
Origin: , and Arabic ṭūfān, deluge (from Greek tuphōn)
Origin: , and Chinese (Cantonese) taaîfung (equivalent to Chinese (Mandarin) tái, great + Chinese (Mandarin) fēng, wind). Word History: The history of typhoon presents a perfect example of the long journey that many words made in coming to English. It traveled from Greece to Arabia to India, and also arose independently in China, before assuming its current form in our language. The Greek word tuphōn, used both as the name of the father of the winds and a common noun meaning “whirlwind, typhoon,” was borrowed into Arabic during the Middle Ages, when Arabic learning both preserved and expanded the classical heritage and passed it on to Europe and other parts of the world. ṭūfān, the Arabic version of the Greek word, passed into languages spoken in India, where Arabic-speaking Muslim invaders had settled in the 11th century. Thus the descendant of the Arabic word, passing into English (first recorded in 1588) through an Indian language and appearing in English in forms such as touffon and tufan, originally referred specifically to a severe storm in India. The modern form of typhoon was influenced by a borrowing from the Cantonese variety of Chinese, namely the word taaîfung, and respelled to make it look more like Greek. Taaîfung, meaning literally “great wind,” was coincidentally similar to the Arabic borrowing and is first recorded in English guise as tuffoon in 1699. The various forms coalesced and finally became typhoon, a spelling that first appeared in 1819 in Shelley's Prometheus Unbound.
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