Pronounced "yock", it combines the words
YACK and TALK, and refers to the
act of just babbling endlessly without much meaningful/legitimate
content.
Radio listener, irritably switching off a live interview of a politician bragging about all the supposed "progress" he's made in his
still-squalid jurisdiction: Okay --- enough of that
BS... got better things to do than listen to HIS yalk for the next two hours!