Marydoll
*Petera*, I stand corrected. I only went back to late 18th century English, but I now know differently.
1711, "an exclusive party of persons; a small set, especially one associating to arrogate power or privilege," from obsolete French clique, which meant originally (14c.) "a sharp noise," also "latch, bolt of a door," from Old French cliquer "click, clatter, crackle, clink,"
I am hanging my head in shame. I can longer claim to be a linguist.
PS, do you want to join our clique? We do make quite a lot of noise! 
Quite appropriate as apparently it comes from claque. It seems claquers were a group of people distributed around an audience to encourage applause. So the sound (and claque is still used for 'slap') become the group of people.
And, it seems, presumably because of the noise, cliques sometimes means 'clogs'.
Just learning this myself so you're only nanoseconds behind me.