Irish leader to put round article: one shilling apiece (9)
I believe the answer is:
taoiseach
'irish leader' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.
'to put round article one shilling apiece' is the wordplay.
'put round' indicates putting letters inside.
'article' becomes 'a' (the indefinite article in English).
'one' becomes 'i' (Roman numeral).
'shilling' becomes 's' (abbreviation e.g. Lsd - pounds, shillings, pence).
'apiece' becomes 'each' (synonyms).
'to' enclosing 'a' is 'tao'.
'tao'+'i'+'s'+'each'='TAOISEACH'
Can you help me to learn more?
(Other definitions for taoiseach that I've seen before include "Irish premier" , "Irish PM" , "Irish head of government" , "Western PM" , "PM in Dublin" .)