Answer:
This is really pretty nasty yet I believe that "having the clap/s" or "The claps" is when someone has an std-I think it's Gonorrhea or something similar. I know it relates to this anyway... Yuk, I know... :0(
Not sure you want to know this, but just in-case this is what your talking about "Echo Clapping" , this is when music is signature based & "clapped to" when a music piece is performed.
Hope this helps in some way... :0)