International Journal of Engineering and Information Systems (IJEAIS)   Year: 2021 | Volume: 5 | Issue: 7 | Page No.: 40-47 Characterization Of Fuzzy Soft Tri-semi-open set In Fuzzy Soft Tri-topological Spaces Asmhan F. Hassan and Azhaar A. Farhan Abstract: In this paper, we define a fuzzy soft tri-semi-open set ( fuzzy soft ?_1 ?_2 ?_3-semi-open set) in a Fuzzy Soft Tri-topological spaces and investigate it is properties, a detailed study is carried out on properties of Fuzzy Soft Tri-semi-interior, Fuzzy Soft Tri-semi-closure of Fuzzy Soft sets and Fuzzy Soft Tri-semi-neighborhood of a Fuzzy Soft point which are fundamental for further research on the theory of Fuzzy Soft Tri-topological spaces (w.r.t. Fuzzy Soft Tri-semi-open set). 2010 AMS Classification: 54A05, 54A10, 54E55, 54E99.