loyal
US /ˈlɔɪ.əl/
UK /ˈlɔɪ.əl/

1.
忠诚的, 忠实的
giving or showing firm and constant support or allegiance to a person or institution
:
•
He is a loyal friend who always stands by me.
他是一个永远支持我的忠诚朋友。
•
The company has a very loyal customer base.
这家公司拥有非常忠诚的客户群。