An idiomatic phrase expressing that if something looks and acts a certain recognizable way, it probably is exactly what it appears to be.
"After the liquor store was robbed, a man was found leaving the scene carrying a gun. Did he commit the crime?"
"If it walks like a duck, looks like a duck, and quacks like a duck, it's a duck."
a fan of spring awakening who is particularly enamored with hanschen/johhny b. wright! the name comes from a quote from the play in which onegirl tells the others "last one to the bridge has to hold hands with hanschen!" therefore, the fans of hanschen would walk very slowly to the bridge.