Definitions of rectify:

• verb:   math: determine the length of

  Example: "Rectify a curve"

• verb:   convert into direct current

  Example: "Rectify alternating current"

• verb:   set straight or right

  Example: "Rectify the inequities in salaries"

• verb:   reduce to a fine, unmixed, or pure state; separate from extraneous matter or cleanse from impurities
• verb:   make right or correct

  Example: "Rectify the calculation"

• verb:   bring, lead, or force to abandon a wrong or evil course of life, conduct, and adopt a right one