A one-day wonder refers to something or someone that is only successful or impressive for a short period. Synonyms for this term may include flash in the pan, one-hit wonder, fleeting success, momentary fame, sudden achievement, ephemeral victory, and passing glory. These phrases highlight the idea that the success is temporary and that it will not last for long. While the initial achievement may be exciting, it often fades quickly, leaving the person or thing forgotten. It is important to distinguish between a one-day wonder and a long-lasting success to ensure sustained growth and success in the future.