Important person on the drink in Tokyo has the same signature as Louis XIII, for example? (8)
I believe the answer is:
namesake
'tokyo has the same signature as louis xiii for example?' is the definition.
I can't judge whether this definition defines the answer.
'important person on the drink' is the wordplay.
'important person' becomes 'name' (name is a kind of important person).
'on' means one lot of letters go next to another.
'the drink' becomes 'sake' (sake is a kind of drink**).
'name'+'sake'='NAMESAKE'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for namesake that I've seen before include "One's similarly entitled" , "One is called after someone" , "One with the same appellation" , "Make sane (anag.)" , "Appellation sharer" .)