2. In this Act, unless there be something repugnant in the subject or context,- "parent" includes the father and mother of a legitimate child, and the mother of an illegitimate child; "guardian" means any person to whom the care, nurture or custody of any child falls by law, or by natural right or recognized usage, or who has accepted or assumed the care, nurture or custody of any child, or to whom the care or custody of any child has been entrusted by any authority lawfully authorized in that behalf; "public vaccinator" means any vaccinator appointed under this Act, or any person duly authorized to act for such public vaccinator; "Inspector” means a person authorized by the Superintendent of Vaccination to exercise all or any of the functions of an Inspector under this Act; "medical practitioner” means any person duly qualified by a diploma, degree or license to practise in medicine or surgery; "unprotected child" means a child who has not been protected from small-pox by having had that disease naturally or by having been successfully vaccinated, and who has not been certified under the provisions of this Act to be insusceptible of vaccination; "unprotected person" includes a child who has no parent or guardian and means a person who has not been protected from small-pox by having had that disease naturally or by having been successfully vaccinated, and who has not been certified under the provisions of this Act to be insusceptible of vaccination; "section" means a section of this Act.