N.Y.C. Charter § 550: Section 550. Definitions.

a. When used in this chapter, the following terms have the following meanings:

Mentally disabled. The term "mentally disabled" means those with mental illness, developmental disability, or addiction disorder, as these terms are defined in section 1.03 of the mental hygiene law, or those with intellectual disability; or any other mental illness or mental condition placed under the jurisdiction of the department by the mayor.

Provider of services. The term "provider of services" means an individual, association, corporation or public or private agency which provides for the mentally disabled.

Services for the mentally disabled. The term "services for the mentally disabled" means examination, diagnosis, care, treatment, rehabilitation, training, education, research, preventive services, referral, residential services or domiciliary care of or for the mentally disabled, not specifically limited by any other law.

b. Notwithstanding the foregoing, planning and programs for persons with substance dependence or chemical dependence shall be conducted by the department, and the department may act as a "local agency" to conduct substance abuse programs and seek reimbursement therefore pursuant to provisions of the mental hygiene law relating to funding for substance abuse services, as deemed appropriate by the commissioner in recognition of the programs currently administered by the New York state office of alcoholism and substance abuse services or its successor agency under article 19 of the mental hygiene law.