A hyphen is used to join two words that are closely connected.Originally Posted by Eway
1. petal-shaped panels (the shape is that of a petal)
2. eight-petal shaped panels (the petal has eight parts)
3. eight-petal-shaped panels (the shape is that of a petal, and the petal has eight parts)
2. and 3. mean the same thing; The second dash in 3. is not necessary:
Examples
1. There are eight panels and they are petal-shaped.
2. There are eight panels and they are eight-petal shaped.
3. There are eight panels and they are petal-shaped, and shape of the petal has eight parts.