a modern economical heating system.
an economic use of home heating oil.
an economical use of her time.
aspects of social, political, and economical life.
economic growth.
economic theory.
gave up the large house for economic reasons.
have to keep prices high enough to make it economic to continue the service.
he wrote the book primarily for economic reasons.
in economic terms they are very privileged.
it was no longer economic to keep the factory open.