There are several synonyms for the phrase "object one's affection." Some of the commonly used ones include "beloved," "darling," "sweetheart," "love interest," and "significant other." These words are often used to refer to someone who is dearly loved or cherished by another person. Some other less common synonyms include "paramour," "flame," and "soulmate." While the term "object one's affection" simply refers to someone who is loved, these synonyms tend to convey a deeper sense of emotion and devotion. They are often used in romantic contexts to express the strong feelings one person has for another.