If you're struggling to find the right words to describe a person who loses interest in something, there are several synonyms that can help you to articulate the feeling more accurately. Some possible alternatives to "loses interest" include the phrases: loses enthusiasm, becomes disinterested, falls out of love, loses focus, loses passion, loses steam, loses momentum, and becomes bored. Each of these synonyms offer a slightly different perspective on the idea of losing interest, and can help to communicate more effectively about how a person's engagement or excitement for a particular activity or object has diminished over time.