腰を据える

こしをすえるkoshiosueru

expression · ichidan verb

1. to settle down (and deal with something)
2. to concentrate all one's energy (on something)
3. to settle oneself (in a place)
4. to settle down (somewhere)
5. to settle in
6. to take a solid stance
7. to lower one's center of gravity (centre)

Study it in Yanamino