1.Definition: (usually followed by `with') well informed about or knowing thoroughly
"Familiar with the complex machinery", "He was familiar with those roads"
2.Definition: having mutual interests or affections; of established friendship
"On familiar terms"
3.Definition: well known or easily recognized
"A familiar figure", "Familiar songs", "Familiar guests"
4.Definition: within normal everyday experience; common and ordinary; not strange
"Familiar ordinary objects found in every home", "A familiar everyday scene", "A familiar excuse", "A day like any other filled with familiar duties and experiences"