From Longman Dictionary of Contemporary Englishsink so lowsink so low (also sink to doing something)BAD BEHAVIOUR OR ACTIONS to be dishonest enough or selfish enough to do something very bad or unfair SYN stoop How could he have sunk so low? → sink
Examples from the Corpus
sink so low• How could he have sunk so low?• Probably because even she had not expected him to sink so low.• Don't let yourself sink so low again - come and talk to me or to the doctor.• Because she had never sunk so low, and never would.• She had not sunk so low as to join the ranks of that sisterhood!• Few bands sink so low, few soar this high. 