/ɒn ɔr əˈbaʊt/ – Phrase
Definition: Xấp xỉ hoặc xấp xỉ vào ngày.
A more thorough explanation: if an event happens on or about 14 May 2009 then it happened sometime near that date, although the exact time and date is not certain (ie it possibly happened on 13 May or 15 May)
Example: Payment was made on or about 14 May.