Formal:
* Shamefaced: This word emphasizes a sense of guilt or humiliation.
* Bashful: This implies shyness and a tendency to avoid attention.
* Modest: This suggests humility and a reluctance to draw attention to oneself.
Informal:
* Self-conscious: This describes someone who is overly aware of themselves and their actions, leading to embarrassment.
* Flustered: This word describes someone who becomes nervous and confused easily.
* Awkward: This suggests clumsiness and a lack of social grace, often leading to embarrassing situations.
* Sensitive: This implies that someone is easily hurt or offended, which can lead to them being embarrassed.
The best word to use will depend on the specific context and the nuance you want to convey.