Final answer:
All the definitions of 'convert' share the common theme of transformation, whether it's in religious beliefs, physical or chemical properties, ideas, or currency exchange. These conversions signify a fundamental change in the state or belief system, echoing a universal concept of transition.
Step-by-step explanation:
What do all these definitions of convert have in common? They all involve a fundamental change in the state, composition, or belief system of the original subject matter. Whether it is changing one's religious beliefs, transforming from one thing into another, altering the physical or chemical properties of something, exchanging currencies, or changing someone's ideas about something, each process involves a transition from one state to another with meaningful and often lasting consequences.
In the context of chemistry, conversion refers to the process where chemical structures are changed to form new products, a concept that aligns with the idea of transformation in the given definitions. Similarly, in the religious context, conversion signifies a profound shift in religious affiliation, often resulting from significant life events or personal choices. This change aligns with the common theme of transition and transformation evident across all definitions of conversion.