There is a big difference between hayaa’ and timidity. 

Timidity is a state of fear due to lack of courage and self-confidence, while hayaa’ is a state of modesty and bashfulness, where the person behaves in a certain way to avoid arrogance and ostentation. 

Hayaa’ is not a state of fear; it is rather a feeling of strength. For example, when the woman displays a modest and bashful behavior (in speaking, walking, dressing, etc.), that gives her a sense of distinction. She therefore feels unique and strong but not arrogant. Hayaa’ is then the opposite of haughtiness and self-conceit, which are unfavorable attributes. On the other hand, timidity is the opposite of courage and bravery, which are favorable characteristics. Source: Friday Naseeha