Skip following lectures and discuss business (4,4)
I believe the answer is:
talk shop
'discuss business' is the definition.
(I've seen this before)
'skip following lectures' is the wordplay.
'skip' becomes 'hop' ('hop' can be a synonym of 'skip').
'following' means one lot of letters go next to another.
'lectures' becomes 'talks' (talk is a kind of lecture).
'hop' after 'talks' is 'TALK SHOP'.
'and' acts as a link.
(Other definitions for talk shop that I've seen before include "Discuss business out of hours" , "Discuss matters concerning one's work" , "like company bosses may do" , "Negotiations" , "dwell on work" .)