| International Civil Aviation Organization | Organizzazione Internazionale dell'Aviazione Civile |
| International Civil Aviation Organization airport code | Codice aeroportuale ICAO |
| international co-operation | cooperazione internazionale |
| International Coalition for the Decade | Coordinamento internazionale per il Decennio |
| International Code of Botanical Nomenclature | Codice Internazionale di Nomenclatura Botanica |
| International Code of Nomenclature of Bacteria | Distinta base |
| International Code of Signals | Codice Internazionale dei Segnali |
| International Color Consortium | International Color Consortium |
| International Cometary Explorer | International Cometary Explorer |
| International Commission on Zoological Nomenclature | Codice Internazionale di Nomenclatura Zoologica |
| International Committee for Weights and Measures | Comité International des Poids et Mesures |
| International Committee of the Fourth International | Quarta Internazionale |
| International Committee of the Red Cross | Comitato Internazionale della Croce Rossa |
| International Communist Current | Corrente Comunista Internazionale |
| international competitiveness | concorrenza internazionale |
| international conflict | conflitto internazionale |
| international convention | convenzione internazionale |
| International Convention for the Safety of Life at Sea | SOLAS |
| International Correspondence Chess Federation | ICCF |
| International Council for Science | International Council for Science |
| International Council of Museums | International Council of Museums |
| International Council on Monuments and Sites | International Council on Monuments and Sites |
| International Court of Justice | Corte Internazionale di Giustizia |
| International Criminal Court | Corte Penale Internazionale |
| International Criminal Tribunal for Rwanda | Tribunale Penale Internazionale per il Ruanda |
| International Cup | Coppa Intercontinentale |
| International Date Line | Linea internazionale del cambio di data |
| International Day for the Eradication of Poverty | Giornata mondiale del rifiuto della miseria |
| international distribution | distribuzione internazionale |
| international division of labour | divisione internazionale del lavoro |
| International draughts | Dama internazionale |
| International Earth Rotation and Reference Systems Service | International Earth Rotation and Reference Systems Service |
| international economic law | diritto internazionale economico |
| International Electrotechnical Commission | Commissione Elettrotecnica Internazionale |
| international environmental relations | relazioni ambientali internazionali |
| International Fairtrade Certification Mark | Commercio equo e solidale |
| International Federation of Library Associations and Institutions | International Federation of Library Associations and Institutions |
| International Federation of Red Cross and Red Crescent Societies | Federazione Internazionale delle Società di Croce Rossa e Mezzaluna Rossa |
| International Finance Corporation | Società finanziaria internazionale |
| International Financial Reporting Standards | International Accounting Standards |
| International Football Association Board | IFAB |
| International for Munich | Monaco di Baviera |
