What is Age Of Consent?

Legal Definition
The age of consent is the age at which a person is considered to be legally competent to consent to sexual acts, and is thus the minimum age of a person with whom another person is legally permitted to engage in sexual activity. The distinguishing aspect of the age of consent laws is that the person below the minimum age is regarded as the victim, and their sex partner as the offender.

The term age of consent rarely appears in legal statutes. Generally, a law will instead establish the age below which it is illegal to engage in sexual activity with that person. It has sometimes been used with other meanings, such as the age at which a person becomes competent to consent to marriage, but the meaning given above is the one now generally understood. It should not be confused with the age of majority, age of criminal responsibility, the voting age, the drinking age, the driving age, etc.

Age of consent laws vary widely from jurisdiction to jurisdiction, though most jurisdictions set the age of consent in the range 14 to 18. The laws may also vary by the type of sexual act, the gender of the participants, or other restrictions such as abuse of a position of trust; some jurisdictions may also make allowances for minors engaged in sexual acts with each other, rather than a single age. Charges resulting from a breach of these laws may range from a misdemeanor such as corruption of a minor, to what is popularly called statutory rape (which is considered equivalent to rape, both in severity and sentencing).

There are many "grey areas" in this area of law, some regarding unspecific and untried legislation, others brought about by debates regarding changing societal attitudes, and others due to conflicts between federal and state laws. These factors all make age of consent an often confusing subject, and a topic of highly charged debates.
-- Wikipedia
Legal Definition
In family law, age of consent refers to the age one can give meaningful consent to enter into a marriage. If over the age of 18 years, meaningful consent is presumed. However the presumption may be negated if the person lacked capacity due to mental retardation, illness for duress.
Legal Definition
the age that a female is legally able to consent to sexual intercourse and or to marriage. This may differ from state to state and some states have a legal age for males too.
Legal Definition
The age below which the law presumes a girl incapable of consenting to the sexual act. See 115 Cal. 132, 46 Pac. 915.
-- Ballentine's Law Dictionary