| 1. | a military movement or advance all the way through and beyond an enemy's front-line defense. |
| 2. | an act or instance of removing or surpassing an obstruction or restriction; the overcoming of a stalemate: The president reported a breakthrough in the treaty negotiations. |
| 3. | any significant or sudden advance, development, achievement, or increase, as in scientific knowledge or diplomacy, that removes a barrier to progress: The jet engine was a major breakthrough in air transport. |
| 4. | constituting a breakthrough: engineered with breakthrough technology; Critics called it a breakthrough film. |
