The most common and most likely answer to this crossword clue is the 5 letter word FEIGN
I've seen this crossword clue in The Daily Telegraph
F
E
I
G
N
More clues leading to the result FEIGN
- Pretend female will get time in power after deposing Queen
- Put on coat for investigating in marsh
- Pretend to be alien – or missing
- Counterfeit offering – any odd bits must go
- Give the appearance of being heard willingly in the past
- Counterfeit fine for king starting rule
- Wife ignores boxing act
- Fake element in penknife ignored
- Put on finger, ring initially removed before adjustment
- Fake knife ignored with packaging removed
Buddy explains!

The straight part
We know that "Fake" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fake = feign.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 FEIGN mean?
FEIGN verb- To make a false show or pretence of; to counterfeit or simulate.
- To imagine; to invent; to pretend.
- To make an action as if doing one thing, but actually doing another, for example to trick an opponent.
- To hide or conceal.