breakthrough

An advance through and past enemy lines.

Any major progress; such as a great innovation or discovery that overcomes a significant obstacle.

“Albert Einstein is credited with making some of the greatest breakthroughs in modern physics.”

The penetration of the opposition defence

The penetration of a separating wall or the remaining distance to an adjacent hollow (a crosscut in mining) or between two parts of a tunnel build from both ends; knockthrough.

Characterized by major progress or overcoming some obstacle.

“a breakthrough technological advance”