The most common and most likely answer to this crossword clue is the 4 letter word MAYA
I've seen this crossword clue in The Guardian
M
A
Y
A
More clues leading to the result MAYA
- Month with a person from Central America
- PM once having a supernatural power?
- Old people blossom with one
- Illusion of S. American people
- Central American is allowed to ask first
- Old people blossom with first bit of activity
- Sail off from Malaysia in a frenzy with supernatural power
- Month with a Yucatan native
- Yucatan native is allowed to answer
Buddy explains!

The straight part
We know that "PM once having a supernatural power? (4)/supernatural power" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case pm once having a supernatural power? (4)/supernatural power = maya.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 MAYA mean?
MAYA noun- Magic; supernatural power as held by the gods.
- The power by which the universe is made to appear; the illusion of the phenomenal world, as opposed to its true or spiritual reality.