invasion
Pluralinvasions
- 1A military operation in which one country's armed forces enter territory controlled by another, usually to conquer land or overthrow its government.
The invasion of the peninsula required months of careful planning.
Coastal defenses were built to repel any future invasion.
Similarincursion, attack, assault, offensive, occupation
Oppositewithdrawal, retreat
Note
This is the sense the others borrow from. An adjective placed before it usually names the invader, not the victim: barbarian invasions, a Chinese invasion, where China is the one coming in. The target follows of, as in the invasion of the peninsula. The word works as a count noun for a single campaign and as a mass noun for the act itself.
- 2The entry of a person or group, without permission, into a space where they are not wanted.
Constant surveillance amounts to a serious invasion of personal privacy.
Residents complained about the invasion of their neighborhood by weekend partygoers.
Similarintrusion, violation, infringement, encroachment, breach
Note
Here the word of changes direction. After the military meaning, of names the territory taken. In this sense it usually names the intruders: an invasion of bees, of mobile phones, of foreign tourists. The crowd is pictured as an army. When of names a space instead, the space is usually something personal, such as privacy or a neighborhood, and the phrase reads as a complaint.
- 3The spread of cancer cells, bacteria, or similar agents into the tissues of the body.
Tumor invasion into the lymph nodes worsened her prognosis.
The invasion of the bloodstream by bacteria can trigger sepsis.
Similarspread, infiltration, penetration
Note
Pathologists rarely use the word bare. They qualify it with whatever the cells have broken into: perineural invasion along nerves, capsular invasion through a tumor's capsule, vascular invasion into vessels. That precision matters, because unequivocal invasion of neighboring tissue is the evidence that lets a growth be diagnosed as a carcinoma, as in Filomena Cetani's 2015 study of parathyroid cancer.
- 4The breaching of the skin barrier, as occurs during a medical or surgical procedure.
Minimally invasive surgery limits the invasion of the skin to a few small incisions.
Each invasion of the skin during the operation was carefully sealed afterward.
Similarbreach, penetration
Note
Surgery has its own, narrower use. The barrier in question is the skin, and the one crossing it is the clinician, not a disease. That sets it apart from the spread of tumors and microbes. A procedure is judged by how much invasion it requires, which is why minimally invasive surgery is described by the size and number of its incisions.
Practice
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Origin
The word comes from Middle French "invasion", which in turn derives from Late Latin "invāsiōnem", the accusative form of "invāsiō".