the area of the body between the ribs and the hips of an animal or a person

the side of something

right/left flank 右／左侧

A small group of houses clings to the eastern flank of the mountain. 一小簇房子紧依山的东侧而建。

to be at the side of someone or something

The president was flanked by senior advisors. 部长们簇拥在总统的两侧。