The phrase "of a sudden" is often spelled and pronounced as "all of a sudden." The word "sudden" is pronounced /ˈsʌdən/ in IPA phonetic transcription, with the stress on the first syllable. The "of" in "of a sudden" is pronounced as /əv/ in IPA transcription, which represents the unstressed form of "have." This is because the phrase originates from the Middle English "of sodaine," which meant "at once." While the phrase has evolved over time, its spelling remains consistent.
The phrase "of a sudden" is an idiomatic expression derived from Middle English. It is mostly used in British English and is generally interchangeable with the more common American English phrase "all of a sudden." It describes an unexpected or abrupt occurrence or change in a situation or event.
Although the phrase may suggest the element of surprise, it does not necessarily imply shock or disbelief. Rather, it emphasizes the rapid or unforeseen nature of the event or action. "Of a sudden" often conveys a sense of immediacy, as if the change or occurrence took place instantly and compelled the attention or reaction of those involved.
For example, one could say, "She turned around, and of a sudden, the car came screeching towards her." This implies that the car appeared suddenly and unexpectedly, catching the person off guard.
In essence, "of a sudden" indicates a swift or abrupt alteration that lacks prior warning or anticipation. It portrays an event that occurs quickly without any prior signals, allowing little time for preparation or response.