Word of the Day:

1 : the fold of skin connecting the forelimbs and hind limbs of some tetrapods (as flying squirrels)

2 : the fold of skin in front of the main segments of a bird's wing

The flying squirrel uses its two patagia to glide from tree to tree.

"One of the key identification marks is the dark leading edge of the wing, called the patagium. These marks on the under wing are only found on the red-tailed hawk." - From an article by Bill Fenimore, The Salt Lake Tribune, February 6, 2012

More example sentences

In Latin, "patagium" referred to a gold edging or border on a woman's tunic, but in English its uses have been primarily scientific. It entered the English language in the early 19th century and was used by entomologists to refer to a process on the back of the foremost segment of an insect. Zoologists borrowed it as a word for the fold of skin of "flying" mammals and reptiles. Then ornithologists took the word to higher heights by the century's end, applying it to the forward part of the wings of birds.