discretion/ dɪs'krεʃən /

1.noun [u] 
(tact) 谨慎

at the discretion of sb
 [frm] 由某人自行处理
to have the discretion to do sth
 [frm] 有做某事的决定权
to use one's discretion
 [frm] 由某人自行决定