خیلی خوش حال بودن
On cloud nine خیلی خوش حال بودن
Whenever a phrase includes a number, like the whole nine yards, at sixes and sevens etc., then attempts to find its derivation usually focus on the significance of the number. ‘On cloud nine’ is no exception.
A commonly heard explanation is that the expression originated as one of the classifications of cloud which were defined by the US Weather Bureau in the 1950s, in which ‘Cloud Nine’ denotes the fluffy cumulonimbus type that are considered so attractive
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