Behind and Fag end

Behind noun - The part of the body upon which someone sits.

Fag end and behind are semantically related In some cases you can use "Fag end" instead a noun "Behind".

Fag end noun - An unused or unwanted piece or item typically of small size or value.

Behind and fag end are semantically related in part topic. Sometimes you can use "Behind" instead a noun phrase "Fag end", if it concerns topics such as tail.