Guard porter possibly charged with base act (9)
I believe the answer is:
beefeater
'guard' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'porter possibly charged with base act' is the wordplay.
'porter possibly' becomes 'beer' (porter is a type of beer).
'charged with' is an insertion indicator (inserted letters charge into others).
'base' becomes 'e' (Euler's number - base of natural logarithms).
'act' becomes 'feat' (feat is a kind of act).
'e'+'feat'='efeat'
'beer' enclosing 'efeat' is 'BEEFEATER'.
Can you help me to learn more?
(Other definitions for beefeater that I've seen before include "Yeoman warder of the Tower of London" , "Tower of London guard" , "no vegetarian?" , "royal bodyguard" , "Royal servant" .)