Usage patterns
〈物〉の末尾に〈物〉をつけるto attach/add something at the end of X
A check digit is added to the end of the number.
〈物〉の末尾に〜と記すto note/write something at the end of a document
I wrote the date at the end of the report.
末尾を切り捨てるto truncate/round down the last digit(s)
The calculation truncates the digits after the decimal point.
〈物〉の末尾が〈物〉と一致するthe end of X matches Y
The end of this file name matches the specified extension.