Private Eye cartoon December 2017.
As predicted in The Business Bullshit Book a few years before.
Yeah yeah yeah: 1. Yes. 2. Irritating way of seeming to acknowledge what the other person is saying, whilst actually patronising them, as in “Yeah I get it you dickhead, now move on to something more interesting.”
BW: 1. Best wishes. 2. Pretty much pointless pair of letters used on email when it would have been just as easy to write best wishes. (see Bz; IMHO; KR; PCB; Tks)
Bz: 1. Busy. 2. Mindless abbreviation of an already-short word, just in order to save writing two letters. (see BW; IMHO; KR; PCB; Tks)