@ Asker 08:31 Nov 27
I don't believe it is simply an 'interlocking' tile — the point here is that it is interlocked only sideways (for mechanical strength not found with plain tiles) BUT that it can be 'slid' up and down to allow a variable spacing (unlike the 'tuiles mécaniques', which impose a fixed spacing in the vertical direction)
I'd have thought something like "vertically-positionable side-interlocking tile", but I've no idea if such a term (and indeed, such a tile!) exists in EN! I think some Marley tiles are of this type (I seem to remember they used them on my house some 35 years ago in the UK), so you might find starting with their website is a good plan — or even give them a ring! | 
peer agreement (net): +1