Mini career break, ultimately a little tedious (7)
I believe the answer is:
irksome
'tedious' is the definition.
(I've seen this before)
'mini career break ultimately a little' is the wordplay.
'ultimately' says to take the final letters.
'a little' becomes 'some' (I've seen this before**).
The last letters of 'mini career break' are 'irk'.
'irk'+'some'='IRKSOME'
(Other definitions for irksome that I've seen before include "Burdensome and tedious" , "bugging" , "Tediously annoying" , "Smokier (anag.)" , "'Annoying, irritating or boring (7)'" .)