rectify (v.)math: determine the length of;
rectify (v.)reduce to a fine, unmixed, or pure state; separate from extraneous matter or cleanse from impurities;
rectify (v.)bring, lead, or force to abandon a wrong or evil course of life, conduct, and adopt a right one;
rectify (v.)set straight or right;
rectify the inequities in salaries
rectify (v.)make right or correct;
rectify (v.)convert into direct current;
rectify alternating current