An amity (noun) is a small, cute mitt, a.k.a., mitten.
There is no precise definition of how small is small when it comes to amities, but it’s generally taken to mean a mitten that is size-appropriate for a child or infant or for a person with hands so small that he or she is often the butt of cruel and insensitive jokes despite not being responsible in any way for his or her small-handedness.
Again, there is no hard and fast delimiter on how young a child must be to call what he or she wears on his or her hands in the winter an amity, but 13 is generally considered to be the upper limit.
Then, of course, there is the “cute” part of the amity definition. Cute is, obviously, a subjective term. One person’s cute is another person’s “revoltingly cutesy”.
The subjective nature of cuteness, along with the lack of precision in qualifying what small means when labeling something as an amity or not, has led to several disputes, some of them violent. This is particularly true when a vendor advertises amities for sale without providing pictures in the ads. If the prospective customers travel a long distance only to arrive and find merchandise that they firmly believe do not qualify as amities battles can ensue.
The inevitable acrimony makes it advisable to stay away from amities altogether.