Almost always used in the negative — 不能姑息 ('cannot tolerate'), 决不姑息 ('absolutely will not tolerate'). The classic four-character set phrase is 姑息养奸 (gūxī-yǎngjiān, 'tolerance breeds villainy').
history
From 《礼记·檀弓上》: '君子之爱人也以德，细人之爱人也以姑息' — 'A gentleman shows love through virtue; a petty person shows love through indulgence.' That classical sense of 'short-sighted leniency' still drives the modern word.
