The most common and most likely answer to this crossword clue is the 6 letter word RELIVE
I've seen this crossword clue in The Daily Telegraph
R
E
L
I
V
E
Buddy explains!

The straight part
We know that "Experience again" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case experience again = relive.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 RELIVE mean?
RELIVE verb- To experience (something) again; to live over again.
- To bring back to life; to revive, resuscitate.
- To come back to life.