The most common and most likely answer to this crossword clue is the 8 letter word DICTATOR
I've seen this crossword clue in Financial Times
D
I
C
T
A
T
O
R
More clues leading to the result DICTATOR
- Autocrat's bizarre act stops journalist dropping leader
- Castro perhaps adroit moving across court
- Detective Murphy talking — he’s in sole charge
- Despot finally read out riot act
- Hitler was a great film for Chaplin
- By the sound of it Richard has overcome King Edward the Tyrant
- Despot‘s schedule withdrawn after decree banishing leader
- Absolute ruler‘s sayings to rankle initially
- Secretary’s boss may be one
- Autocrat reversed corruption at police department
Buddy explains!

The straight part
We know that "Castro perha/p/s" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case castro perha/p/s = dictator.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DICTATOR mean?
DICTATOR noun- A totalitarian leader of a country, nation, or government.
- A magistrate without colleague in republican Ancient Rome, who held full executive authority for a term granted by the senate (legislature), typically to conduct a war.
- A tyrannical boss or authority figure.
- A person who dictates text (e.g. letters to a clerk).