IPA: /ˈdʒʌdʒ.mən.təl/
KK: /ˈdʒʌdʒməntəl/
Having a tendency to form opinions about others, often in a critical or disapproving way.
She was often judgmental about people's choices, which made her friends uncomfortable.
Judgmental is formed from "judge" (from Latin "judicare", meaning to judge or decide) and the suffix "-mental" (meaning relating to or pertaining to). The word describes a tendency to make judgments about others.
Think of the act of 'judging' someone and how 'mental' relates to thinking — that's why judgmental means relating to making judgments about others.