IPA: /nɒnˈmɛmbə/
KK: /nɑnˈmɛmbər/
A person or thing that does not belong to a particular group or organization.
As a nonmember, she could not access the exclusive events held by the club.
Nonmember → It is formed from "non-" (meaning not) and "member" (from Latin "membrum", meaning a part or limb). The word "nonmember" refers to someone who is not a part of a group or organization.
Think of 'non-' meaning 'not' and 'member' meaning 'part' — so a nonmember is someone who is not a part of a group.