French word surinfection comes from French surmonter, French infection ((pathology) infection.)

Detailed word origin of surinfection

Dictionary entry	Language	Definition
surmonter	French (fra)	(transitive) to overcome, to surmount, to get over. (transitive) to top, to crown (a building, etc.).
infection	French (fra)	(pathology) infection.
surinfection	French (fra)	Superinfection, secondary infection.