These words describe the character or behaviour of a person who defies convention or authority, and are often used in reference to children. Mischievous is to be found in connection with the playful, teasing, but nonetheless irritating behaviour that is part of every child’s make-up at one time or another. It suggests that the harm done or trouble caused is neither lasting nor severe: The mischievous boy went through the house hanging all the pictures upside-down. When used to characterize an adult, however, mischievous suggests a manner or action that is more troublesome than playful, more harmful than teasing: a mischievous gossip who broke up his marriage by spreading rumours about his wife.

Naughty is commonly used by adults when speaking of a child’s misbehaviour, and, sometimes, humorously, when speaking of the sexual attraction or peccadilloes of another adult.

• You were a naughty boy, Johnny, breaking your sister’s doll that way; an actress who built her reputation on being "naughty but nice."

Although the application of naughty to children is usually confined to instances of trivial breaches of conduct, it is sometimes used to refer to more reprehensible action and in such cases can be considered a euphemism for certain senses of bad . Bad is a very broad word. It can at times he interchangeable with the most innocent connotations of mischievous .

• What a bad little girl you are, smearing jam all over mummy’s new dress.

But it may also describe a child (and, of course, an adolescent or adult) who is wilful, intractable, immoral or evil.

Delinquent as an adjective means neglectful of duty or obligation: a delinquent father who spent more time playing poker than playing with his children. This meaning is not very often found in reference to children or young people, possibly because of the very common use of the word in the expression juvenile delinquent , which means a young person guilty of anti-social or criminal behavour. It is unfortunate that this expression, which is specific in tone and pejorative in connotation, is applied loosely to young people who are indeed not juvenile delinquents but merely mischievous , bad or disobedient .

Disobedient is another broad word. It refers simply to a failure or a refusal to obey, but its connotations when it is used to describe a child are different from those applying to an adult. Very young children who are characterized as disobedient might instead be called mischievous or naughty ; they are rarely guilty of any serious misbehaviour, and their failure or refusal to obey is more an act of will than of reason. Older children, adolescents and adults, however, who are disobedient may be guilty of a major oversight or transgression: a disobedient student who was forced to leave boarding school; a habitually disobedient soldier who was finally court-martialled after he struck his commanding officer.