watertight

She urged the council to take immediate action to make the building watertight and windproof.

"The legislation must be watertight and without loopholes that could be used by those wanting to delay the rights workers so desperately need," he said.

As descriptions of biological processes go, this model looked watertight.

"At the bottom water oozed through the iron sides of the great tube, which has never been totally watertight. At one place a single stalactite a foot long hung from the roof."

Skin is also a watertight barrier, the first line of defense against the outside world.