Extensive :

Expensive : costing a lot of money.
Compact : closely and neatly packed together, dense.
Concrete : existing in a material or physical form; not abstract.
Abstract : existing in thought or as an idea but not having a physical or concrete existence.
Narrow : of small width in relation to length, limited in extent, amount, or scope.
Extensive : covering or affecting a large area, large in amount or scale.

Antonym of Extensive is Narrow.