[v] convert into direct current; "rectify alternating current"
[v] make right or correct; "Correct the mistakes"; "rectify the calculation"
[v] set straight or right; "remedy these deficiencies"; "rectify the inequities in salaries"; "repair an oversight"
[v] bring, lead, or force to abandon a wrong or evil course of life, conduct, and adopt a right one; "The Church reformed me"; "reform your conduct"
[v] reduce to a fine, unmixed, or pure state; separate from extraneous matter or cleanse from impurities; "refine sugar"
[v] math: determine the length of; "rectify a curve"