Posted in Dictionary DSSI stands for Diplôme en Sécurité des Systèmes d’Information (French: Diploma in Information Systems Security; Switzerland) DSSI stands for Disposable Soft Synth Interface (software) DSSI stands for Diversified Scientific Services, Inc. DSSI stands for Digital Storage Systems Interconnect DSSI stands for Data Systems and Software Inc. (Mahwah, NJ) DSSI stands for Dyspepsia Symptom Severity Index DSSI stands for Dead Sea Scrolls Institute (Trinity Western University, Canada)