Reflexive verbs are verbs whose object is the same as the subject. The object is called a reflexive pronoun.

Example:
Er wäscht sich nicht mehr.

Many verbs can be used reflexively or non-reflexively with an accusative object. In German these are called "unecht" or "false" reflexive verbs.

Examples:
Er wäscht sich nicht mehr. – Er wäscht die Hände nicht mehr.
Er kämmt sich nicht mehr. – Er kämmt seine Haare nicht mehr.

Other verbs, however, are exclusively reflexive. Such verbs cannot be used without the reflexive pronoun. Nor can the reflexive pronoun be replaced by another pronoun or noun. In German these are called "echt", or "true", reflexive verbs.

Examples:
Beeil dich!
Ich beeile mich.