Assertion: duck's gland | /r/HasProperty | uropygial
Facets:
Source sentences:
text: During preening, ducks spread a waxy, waterproof oil secreted by their uropygial gland, which is located near their tails.
text: During preening, ducks spread a waxy, waterproof oil secreted by their uropygial gland, which is located near their tails.