initialism of Institut Géographique National (the French national geographic institute, now called Institut national de l'information géographique et forestière)
acronym of Institut national canadien pour les aveugles (“Canadian National Institute for the Blind”): CNIB; acronym of Institut national du cancer (“National Cancer Institute”)
acronym of Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (“National Institute of Agricultural, Alimentary, and Environmental Research”)
abbreviation of Institut de Radioastronomie Millimétrique (international research institute and first European center for millimetre-wave radio astronomy)
Icarus (a Greek mythological figure, son of Daedalus, who escaped from the Cretan labyrinth of Knossos by flying with wings made from feathers and wax, but flew too near to the sun, which melted the wax in the wings, so he fell down and drowned in the Aegean Sea)
Ishim (a town in Tyumen Oblast, Russia); Ishim (a left tributary of the Irtush River flowing 1,520 miles through Kazakhstan and Russia and passing through Astana, capital of Kazakhstan)
Illyria (a vaguely-defined geographic region in Southeastern Europe in the western part of the Balkan Peninsula, approximately coincident with modern Albania); Illyria, Illyricum (a much larger former province of the Roman Empire, covering the whole of Dalmatia and Pannonia, existing from 27 BC to c. 70 AD and reconstituted in 293 AD by Diocletian)