rec·ti·fy (rkt-f)
tr.v. rec·ti·fied, rec·ti·fy·ing, rec·ti·fies

1. To set right; correct.
2. To correct by calculation or adjustment.
3. Chemistry To refine or purify, especially by distillation.
4. Electronics To convert (alternating current) into direct current.
5. To adjust (the proof of alcoholic beverages) by adding water or other liquids.

(The Free Dictionary by Farlex 2011)

rectify (‘rektəˌfī) vb. –fies, -fying, -fied. (tr.)

1. to put right; correct; remedy
2. to separate (a substance) from a mixture or refine (a substance) by fractional distillation
3. to convert (alternating current) into direct current
4. Maths. To determine the length of (a curve)
5. to cause (an object) to assume a linear motion or characteristic. (C14: via Old French from Medieval Latin rectificare rēctificāre to adjust, from Latin rectus rēctus straight + facere to make) – ,recti’fiable adj. – ,rectifi’cation n.

(The Collins Dictionary Of The English Language Second Edition 1986)

rec’tify, v.t. 1. Put right, correct, amend,
reform, adjust, (method, calculation,
statement, position, instrumental) 2.
Abolish, get rid of, exchange for what is
right, (abuse, anomaly, error, omission,
grievance). 3. (chem.). Purify or refine
by renewed distillation or other process.
4. (geom.) Find straight line equal to
(curve). Hence or cogn. ~fiER

(The Concise Oxford Dictionary of Current English, Fifth Edition 1964)