Idiom of the day :- Have a nodding acquaintance

Usage, examples and definition of the Idiom :-

When passing people we know only slightly, we sometimes politely nod our heads at them. From that comes this idiom which means to know a person or a subject only slightly. ‘I have a nodding acquaintance with my neighbors,’ Brian said. ‘I only have a nodding acquaintance with the works of Rembrandt,’ Cameron said.