Shirttails

noun

1. The single or split (then rather plural) bottom part of a shirt, below the waist, especially in the back, which, when not tucked into trousers or other vestment, hangs over the wearer's tail-end, like a tail.
2. (by extension) The tail-end or periphery of something.
3. A tenuous connection.
4. A distant kinship.
5. A small portion