Not initially dominating, bringing son in all the time (3-4)
I believe the answer is:
non-stop
'all the time' is the definition.
(I've seen this before)
'not initially dominating bringing son in' is the wordplay.
'initially' says to take the initial letters.
'dominating' becomes 'ontop' (I can't justify this - if you can you should give a lot more credence to this answer).
'bringing' means one lot of letters go next to another.
'son' becomes 's' (genealogical abbreviation for son).
'in' is an insertion indicator.
The initial letter of 'not' is 'n'.
'n'+'ontop'='nontop'
'nontop' going around 's' is 'NON-STOP'.
Can you help me to learn more?
(Other definitions for non-stop that I've seen before include "Uninterrupted" , "Round-the-clock" , "Going straight from A to B" , "Continuous" , "Ceaseless" .)