Dichloro- is a prefix that is used in chemistry to denote the presence of two chlorine atoms in a molecule. There are many synonyms for dichloro-, including di-, bis-, and bis(chloro-). These synonyms are often used interchangeably, and they all have the same meaning. The use of these synonyms allows chemists to easily identify the presence of two chlorine atoms in a molecule, without having to write out the full word. This is important for simplifying chemical formulas and for ensuring accurate communication of chemical information. Overall, the synonyms for dichloro- are an important tool for chemists to use in their work.