The term SEED COVERING can be broken down into four crossword solutions: ARIL (4 letters), TESTA (5 letters), POD (3 letters), and HULL (4 letters). An ARIL is a fleshy or brightly colored covering that surrounds some seeds, such as those of the yew tree. A testa is the outer layer of a seed, which is often hard and protects the inner contents. A POD is a dry, dehiscent fruit that splits open to release its seeds. Finally, a HULL is the outer covering of a seed, which is usually thin and papery.