Tetrad is a scientific term commonly used in genetics to refer to a group of four molecules or chromosomes. However, there are several other synonyms that can be used instead of tetrad. These include quad, quartet, foursome, quadruple, and fourfold. In the field of chemistry, tetrad is sometimes used to refer to a molecule with four functional groups. In this context, other synonyms for tetrad include tetramer, tetravalent, and tetratomic. While these terms may be interchangeable in some contexts, it's important to use the appropriate word based on the particular scientific discipline and context of the information being conveyed.