is a specific kind of: plant order.

is a broader term that covers: Ericaceae, family Ericaceae, heath family.

has as a member: Clethraceae, family Clethraceae, white-alder family | diapensia family, Diapensiaceae, family Diapensiaceae | Epacridaceae, epacris family, family Epacridaceae | family Lennoaceae, Lennoaceae | family Pyrolaceae, Pyrolaceae, wintergreen family | family Monotropaceae, Monotropaceae.

is a member of: Dilleniidae, subclass Dilleniidae.