Gunawan, HendraMashadiGemawati, SriNursupiaminSihwaningrum, Idha2016-02-172016-02-172016-02-17wahyu sari yenihttp://europeana.eu/portal/record/92040/BibliographicResource_1000095954366.htmlhttp://repository.unri.ac.id/xmlui/handle/123456789/7930In this paper we discuss some existing notions of orthogonality in 2-normed spaces and their drawback. We also formulate new de¯nitions of orthogo- nality that improve the existing ones. In the standard 2-normed space, our notions of orthogonality coincide with the usual one.enorthogonality2-normed spaces2-inner product spacesUR-Scientific Work Lecturer