<p><strong>Noun</strong></p><ul><li>a military movement or advance all the way through and beyond an enemy's frontline defense</li><li>an act or instance of removing or surpassing an obstruction or restriction; the overcoming of a stalemate</li><li>The president reported a breakthrough in the treaty negotiations</li><li>any significant or sudden advance, development, achievement, or increase, as in scientific knowledge or diplomacy, that removes a barrier to progress</li><li>The jet engine was a major breakthrough in air transport</li><li>Medicine/Medical: an infection, disease, disorder, or condition that occurs in an individual despite their having received a vaccine, medication, or treatment</li><li>Covid breakthroughs are usually less severe than infections in unvaccinated people, indicating that the vaccine is still doing its job of combating the virus</li></ul><p><strong>Adjective</strong></p><ul><li>constituting a breakthrough</li><li>Critics called it a breakthrough film</li><li>Their products are engineered with breakthrough technology</li><li>Medicine/Medical: relating to or being an infection, disease, disorder, or condition that occurs as a breakthrough</li><li>She experienced disabling breakthrough pain despite the high dose of painkillers she was taking</li><li>In the original vaccine trial, 89% of breakthrough infections were with a particular family of virus strains</li></ul>