CIS is an abbreviation for the term "Collective Information Source".
A collective information source is an educational resource with information specific to a certain subject; it is usually held in a binder or folder.
A CIS can be created for general
educational purposes, as a place to gather ones arguments during a disagreement, or out of pettiness.
This abbreviation is not to be confused with any of the following:
Cisgender, The Center for Immigration Studies, The Commonwealth of Independent States, The Council of International Schools, The Center for Internet Security, Canadian Interuniversity Sport, The Corpus Inscriptionum Semiticarum, Carcinoma
in situ, The Center for Comparative and International Studies, The Knabenchor collegium iuvenum
Stuttgart, a continuous ink system, a copper
indium selenide solar cell, a contact image sensor, The Confederacy of Independent Systems, the towns in Italy and Poland, the mathematical function, the Cis beetle, cis regulatory elements, cis isotope alkenes, cisalpine, and the C#
music note.