This is probably a silly question, but I've always been under the impression that 'abt' means 'about'.
eg. abt 1887
Just out of interest if there is a written document stating a year, why then add 'abt' to the date. Is this because that a lot of documents through history have been proven wrong, or were the people writing the documentation throughout history always playing catchup to get the documents such as census's written.
What would be a safe year bracket to use when looking at dates? Should we be exact with a year, or if we have a feeling that something just doesn't add up, but still maybe correct. Should we still go ahead and use the document.