Modesty (noun)

1. The quality of being unassuming and moderate in the estimation of one's abilities or achievements.
2. The quality of having or showing a moderate appreciation of one's own abilities or worth.
3. A lack of pretentiousness or showiness in dress, speech, or behavior.

Origin:

Late 16th century, from the latin modestia, from modus, meaning "measure".

Examples:

1. Her modesty was one of her most endearing qualities.
2. The new building is designed with the utmost modesty and simplicity.
3. Her dress was modest and practical.
4. He was known for his modesty, despite his great success.
5. He was surprised by the modesty of her request.