As used in this act: a. "Employee" includes any person, either male or female, employed by an employer, but shall not include persons performing volunteer service for nonprofit organizations or corporations nor persons employed on a farm, or in domestic service in a private home, or in a hotel. b. "Employer" includes any person acting directly or indirectly in the interest, or as agent, of an employer in relation to an employee and further includes one or more individuals, partnerships, corporations