SISD

SISD can refer to:


 * Single instruction, single data, a computer processor architecture
 * CCL5, an 8kDa protein also using the symbol SISD
 * Sixteen-segment display
 * Several school districts in Texas. See List of school districts in Texas - S
 * Saginaw Intermediate School District (Michigan)
 * Southeast Island School District (Alaska)
 * Swiss International Scientific School in Dubai