The phrase "over modest" typically implies that someone is excessively humble or downplays their accomplishments. Antonyms for this phrase include "arrogant," "conceited," "boastful," and "egotistical." These words suggest a person who is overly confident and self-important. Other antonyms include "showy," "flashy," and "ostentatious," which convey a sense of pretentiousness and an exaggerated desire to impress others. While being too modest can be a hindrance, being too boastful can also be seen as negative. It is important to strike a balance between being confident and humble, and using language appropriately to convey this balance.