layperson

/ˈleɪpɜːsən/ noun [C] (plural laypeople) (also layman (plural laymen))

Definition

› someone who is not an expert in or does not have a detailed knowledge of a particular subject: Any layperson can sit down at this console and begin doing productive work in minutes. To the layman these rules may seem unnecessarily complex. Can you explain in layman's terms exactly what your job involves?

(Definition of layperson noun from the Cambridge Business English Dictionary © Cambridge University Press)