General synonyms:
* Unassuming: This suggests a lack of pretension or arrogance.
* Modest: This implies humility and a lack of desire for attention.
* Humble: Similar to "modest," but often with a stronger sense of recognizing one's own limitations.
* Subdued: This suggests a quiet and understated demeanor.
* Retiring: This implies a preference for privacy and avoidance of social situations.
* Discreet: This emphasizes the act of being careful not to draw attention to oneself.
* Unpretentious: This suggests a lack of artificiality or affectation.
More specific synonyms:
* Selfless: This highlights the act of putting others' needs before one's own.
* Deferential: This emphasizes respect for others and a willingness to yield to their opinions.
* Obscure: This suggests a tendency to remain unnoticed or unknown.
Antonyms:
* Showy: The opposite of self-effacing, suggesting a desire for attention and a flamboyant personality.
* Boastful: This implies bragging and an inflated sense of self-importance.
* Egotistical: This refers to excessive self-centeredness and a lack of regard for others.
The best synonym for "self-effacing" will depend on the specific context and the particular quality you want to emphasize.