The penetration of the opposition's defence.
An advance through and past enemy lines.
Any major progress; such as a great innovation or discovery that overcomes a significant obstacle.
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.
Involving the contraction of a disease by a person with a decreased susceptibility, such as a person who has been vaccinated to help prevent that disease.
Characterized by major progress or overcoming some obstacle.
The emergence or one or more symptoms of a condition despite medication or other medical treatment.
Offering to an opponent a choice between two (equally unfavorable) alternatives.
A difficult circumstance or problem.
A type of syllogism of the form "if A is true then B is true; if C is true then D is true; either A or C is true; therefore either B or D is true".
A circumstance in which a choice must be made between two or more alternatives that seem equally undesirable.