chief ingredient

“The chief ingredient in that stuff is rum,” she avowed to me as we walked home, stretching up her neck in displeasure.

Its composition is a trade secret, but its chief ingredient is rubber.

The Indian finds in the wilds a vine called Wourali, which furnishes the chief ingredient.

It is also used in considerable quantities in the manufacture of soy, the chief ingredient of which is beans.

It is the chief ingredient in sealing-wax, and is extensively used as a varnish.