What is the difference between 'de-noising' and what we commonly know as filtering methods to remove noise? Pretty simple question - I am trying to figure out what exactly is different between 'de-noising' a signal, and simply filtering it (as we commonly know) to remove noise. Is this a case of lexical overlap or is there something fundamentally different? Why is it called 'de-noising'? 

Edit: Perhaps crucially, when we talk of filtering a signal to maximize its SNR, we usually mean AWGN in the colloquial context. So is the 'noise' being referred to in de-noising also AWGN, and if so, is de-noising simply a different way of removing it, or is it a different type of noise (non-gaussian, colored, etc) to begin with?
De-noising is about the goal, and filtering is about the technique you employ. 

You can obviously de-noise via filtering. For example, if you know that your system cannot transmit frequencies above a certain threshold, you can apply a low-pass filter. However, you can de-noise by other techniques as well, such as by averaging multiple recordings of a signal. Similarly, you can apply filters with other goals than (just) noise reduction. 

Note that "noise" may not necessarily be additive random noise - depending on your context, non-pertinent signals may be lumped with noise as well, such as the sound of vuvuzelas.