'colonial institutions' is correct and usable in written English.
You can use it when referring to systems and organizations established and maintained by a colonizing power in a colony. For example, "In the early 19th century, colonial institutions in India included the East India Company."
Colonial institutions decay, hedges become overgrown and then are cut down.
During the 19th century, many countries established new secondary schools on the basis of colonial institutions.
Having inherited colonial institutions devoid of indigenous symbols of national identity, many independent African governments invested considerable economic and political capital into national football teams in order to elicit pride and build unity among their diverse populations.
When we speak of Calcutta's architecture, we usually mean the colonial institutions that the British erected, or the aristocratic mansions of North Calcutta (once called the "Black Town" by the English) built by Bengali landowners.
Some of the other remains held in the boxes at Mitchell (which I'm not permitted, out of deference to the dead, to open) belong to Indigenous Australians who died in colonial institutions – jails, hospitals and asylums – and, scarcely cold, were "anatomised" (a benign euphemism for butchery).
Both as part of their ideological commitment to liberal individualism and as a means of increasing the power of their new states, leaders in the postindependence years tried to establish their control over the formidable colonial institutions of the Roman Catholic Church and the military.
They wonder whether such a colonial institution is appropriate in 2005.
After partition, the National College of Arts was forged from an existing colonial institution, and schools were also established in other cities.
In Indonesia, deposits grew sixfold last year, as savers flocked out of domestic banks into the perceived safety of a "colonial" institution.
The long-term implications of pre-colonial institutions in Africa have been discussed among others by Manning (1990), Herbst (2000), Bockstette et al. (2002), Gennaioli and Rainer (2007), and Michalopoulos and Papaioannou (2013).
The west African nation branded the 54-member grouping, which includes the UK and most of its former colonies, a "neo-colonial institution".
