The most common and most likely answer to this crossword clue is the 6 letter word HURDLE
I've seen this crossword clue in The Daily Telegraph
H
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More clues leading to the result HURDLE
Buddy explains!
The straight part
We know that "Barrier" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case barrier = hurdle.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 HURDLE mean?
HURDLE noun- An artificial barrier, variously constructed, over which athletes or horses jump in a race.
- A perceived obstacle.
- A movable frame of wattled twigs, osiers, or withes and stakes, or sometimes of iron, used for enclosing land, for folding sheep and cattle, for gates, etc.; also, in fortification, used as revetments, and for other purposes.
- A sled or crate on which criminals were formerly drawn to the place of execution.
- To jump over something while running.
- To compete in the track and field events of hurdles (e.g. high hurdles).
- To overcome an obstacle.
- To hedge, cover, make, or enclose with hurdles.