Breakthrough (noun)

1. A significant development or improvement.
2. A major advance in knowledge or technology.
3. A sudden and dramatic increase in understanding or ability.
4. A military or strategic gain that penetrates and collapses an enemy's defensive line.

Origin:

Mid 19th century: from break + through.

Examples:

1. The discovery of the new element was a major breakthrough in the field of chemistry.
2. The breakthrough in the negotiations resulted in a new trade agreement.
3. The new medication was a breakthrough in the treatment of the disease.
4. The athlete's breakthrough performance was a personal best.
5. The breakthrough of the military campaign was a turning point in the war.