I. ˈshərt-ˌtāl noun
Date: 1809
1. : the part of a shirt that reaches below the waist especially in the back
2. : something small or inadequate
II. adjective
Date: 1845
1. : very young : immature
shirttail boys fishing in the creek
2. : distantly and indefinitely related
a shirttail cousin on her father's side
3. : small, trivial, or short typically to the point of inadequacy
has a gullied shirttail ranch in the hills