Sexual abuse of a child is generally defined as physical contact or other interaction between a child (under age 17, for example) and an adult when the child is being used for the sexual stimulation or pleasure of the perpetrator or another person. In addition to physical contact, sexual abuse of a child may include (1) the exposure of the genitals of an adult in the presence of a child, (2) the exposure of the genitals of a child, (3) using a child in making pornography, or (4) making a child view sexual acts or pornography.

And in some states multiple instances of sexual contact between an adult and a child may constitute the enhanced criminal offense of continual sexual abuse of a child—which is sometimes a first-degree felony offense.

In California, sexual abuse of a child is addressed under various statutes that criminalize acts such as lewd or lascivious acts with a child under 14 years of age (California Penal Code 288), sexual exploitation of a child (California Penal Code 311.3), and using a minor for sex acts (California Penal Code 311.4). The state defines a child as a person under the age of 18 for these offenses. California also recognizes the specific offense of continuous sexual abuse of a child under California Penal Code 288.5, which involves repeated sexual abuse of a child under the age of 14 by someone who has lived with or had recurring access to the child. This offense is considered a felony and can result in severe penalties, including imprisonment. The law is designed to protect minors from sexual exploitation and abuse, and it imposes strict penalties on those who violate these provisions.