Aphorismus
Aphorismus (from the , aphorismós, "a marking off", also "rejection, banishment") is a figure of speech that calls into question if a word is properly used ("How can you call yourself a man?"). It often appears in the form of a rhetorical question which is meant to imply a difference between the present thing being discussed and the general notion of the subject. Examples
"For you have but mistook me all this while. / I live with bread like you, feel want, / Taste grief, need friends: subjected thus, / How can you say to me I am a king?" William Shakespeare, Richard II Act 3, scene 2, 174-177
"It depends on what the meaning of the word 'is' is." Bill Clinton, August 17, 1998

See also
Figure of speech

References 

Figures of speech