"Elective affinity" is a phrase often used to describe a strong attraction or connection between two things, people, or ideas. There are several synonyms for this phrase that can be used to convey a similar meaning. For instance, the phrase "kindred spirits" may be employed to describe two people who share a strong affinity or connection. Meanwhile, "chemistry" might be used to convey the unexplainable attraction or spark between two people. Other potential synonyms for "elective affinity" include "synergy," "kinship," "comradeship," and "rapport." Each of these words can help to express the idea of a powerful and meaningful connection between two entities.