Low-key (adjective)

1. Not very intense or dramatic.
2. Understated or subdued in nature.
3. Not drawing attention to oneself.

Origin:

Low-key is a compound of the words "low" and "key", which refers to something that is not very intense or dramatic.

Examples:

1. They decided to have a low-key wedding ceremony, with just a few close friends and family in attendance.
2. She wanted to wear something low-key for her graduation ceremony, so she chose a simple dress.
3. The party was supposed to be low-key, but it ended up getting out of hand.
4. He kept his reaction low-key, even though he was really excited.
5. She had a low-key personality, which made it easy for her to blend in with any crowd.