With an initial dividend (3)
I believe the answer is:
and
'with' is the definition.
'an initial dividend' is the wordplay.
'initial' indicates taking the first letters.
The first letter of 'dividend' is 'd'.
'an'+'d'='AND'
(Other definitions for and that I've seen before include "In addition" , "It connects words, clauses or sentences" , "Joining word" , "Also" , "See 20" .)