gap

An opening in anything made by breaking or parting.

"He made a gap in the fence by kicking at a weak spot."

An opening allowing passage or entrance.

"We can slip through that gap between the buildings."

An opening that implies a breach or defect.

"There is a gap between the roof and the gutter."

To notch, as a sword or knife.

To make an opening in; to breach.

To check the size of a gap.

"I gapped all the spark plugs in my car, but then realized I had used the wrong manual and had made them too small."