The support facilities and services for
a community, such as roads, parks, sewers, water,
schools, trash collection, etc.
Merriam-Webster Online Dictionaryinfrastructure
the underlying foundation or basic framework (as of a system or organization)
the permanent installations required for military purposes
the system of public works of a country, state, or region , also the resources (as personnel, buildings, or equipment) required for an activity