at that

1. In addition, besides, as in The seats were good, and quite cheap at that . [First half of 1800s]

2. In spite of, nevertheless, as in Although I had to wait a long time for delivery, it was worth it at that . [Mid-1800s]

3. As it stands, without further changes, as in She wasn't happy with her grade in the course but decided to leave it at that . [Late 1800s]