One-off is a "partially Latin" phrase that literally means "only one." In the current Italian language, an event occurs one and only time.
Often, the expression is mistakenly used or meant to indicate an occurrence occurring sporadically, thus attributing the meaning of "once in a while", probably by virtue of the assonance with this Italian phrase. Typical cases of a wikitesto tantum modification
One-off usage is also used with tariff plans for different phone operators. Notemodify wikitesto
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