Definition of development noun from the Oxford Advanced Learner's Dictionary
1[uncountable]the gradual growth of something so that it becomes more advanced, stronger, etca baby's development in the wombthe development of basic skills such as literacy and numeracycareer development
2[uncountable, countable]the process of producing or creating something new or more advanced; a new or advanced productthe development of vaccines against tropical diseasesdevelopments in aviation technologyThis piece of equipment is an exciting new development. see also research and development
3[countable]a new event or stage that is likely to affect what happens in a continuing situationthe latest developments in the warAre there further developments in the investigation?
4[countable]a piece of land with new buildings on ita commercial/business/housing development see also ribbon development5[uncountable]the process of using an area of land, especially to make a profit by building on it, etcHe bought the land for development.