IPA: /nɒnˈfæmɪliəl/
KK: /nɑnˈfæmɪliəl/
Not related to family or relatives; not familial in nature.
The study focused on nonfamilial relationships among the participants.
Nonfamilial → It is formed from "non-" (meaning not) and "familial" (from Latin "familialis", meaning relating to family). The word "nonfamilial" means not related to or characteristic of a family.
Think of 'non-' meaning 'not' and 'familial' relating to 'family' — so nonfamilial describes something that is not connected to family.