To Affect

1. (transitive) To influence or alter. Synonyms: alter, change, have an effect on, have an impact on, influence
2. (transitive) To move to emotion. Synonyms: move, touch
3. (transitive, pathology) Of an illness or condition, to infect or harm (a part of the body).Synonyms: attack, harm, infect
4. (transitive, archaic) To dispose or incline.
5. (transitive, archaic) To tend to by affinity or disposition.
6. (transitive, archaic) To assign; to appoint.
7. (transitive) To make a show of; to put on a pretense of; to feign; to assume. To make a false display of. [from 16th c.] Synonyms: fake, simulate, feign
8. (obsolete, transitive) To aim for, to try to obtain. [15th-19th c.]
9. (transitive, rare) To feel affection for (someone); to like, be fond of. [from 16th c.]
10. (transitive, obsolete) To show a fondness for (something); to choose. [from 16th c.]

Usage notes

Affect and effect are sometimes confused. Affect conveys influence over something that already exists, but effect indicates the manifestation of new or original ideas or entities:

• "...new policies have effected major changes in government."
• "...new policies have affected major changes in government."

The former indicates that major changes were made as a result of new policies, while the latter indicates that before new policies, major changes were in place, and that the new policies had some influence over these existing changes.

The verbal noun uses of affect are distinguished from the verbal noun uses of effect more clearly than the regular verb forms. An affect is something that acts or acted upon something else. However, an effect is the result of an action (by something else).