Différance
Différance is a term that Derrida coins on the basis of a pun that the French language makes possible. An understanding of this term is helpful because it can explain a lot about Derrida’s apparently “mischievous” playing with language and ideas. I put “mischievous” in quotation marks because many people have misunderstood the powerful implications of his witty strategy.
The pun is possible because in French the word différer can mean either to differ or to defer, depending on context. Différence can mean to differ from something or to defer something.
If I was comparing two different objects of the same generic type (this hat is different from this one) I’d use différer just as I would if I was putting off an appointment (let's defer it until a time when we’ll both be free). The one, take note, implies spatiality (difference), the other implies temporality (deferral). What Derrida is asking us to do is to combine both, normally mutually exclusive, meanings in the one new term différance. Because the term has passed into the English language (at least in theoretical registers) I’ll not be maintaining the italicised and accented French form from now on. The pun involves the use of the little letter “a.” The French différence might mean either difference or deferral.
Derrida’s new term, spelt with an “a” instead of an “e,” should be taken to mean both difference and deferral simultaneously. The first part of the pun we can call the performative--or auto-referential--aspect. What this means is that by both differing from itself (it means two different things at once) and deferring until infinity any final meaning (it cannot at any one time mean both differ and defer) the word itself is a performance of its meaning. Differance just is what differance means.
http://courses.nus.edu.sg/course/elljwp/differance.htm
