Expressions (phrases, clauses, etc.), Ichidan verb
to settle down (and deal with something); to concentrate all one's energy (on something)
彼はその仕事に腰を据えている。He has settled down to the job. to settle oneself (in a place); to settle down (somewhere); to settle in
to take a solid stance; to lower one's center of gravity (centre)
Also written 腰をすえる【こしをすえる】