The most common and most likely answer to this crossword clue is the 8 letter word HANDICAP
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result HANDICAP
- Disability assistance I put an upper limit on
- Possibly scratch hamstring
- Convenient-sounding cover for the Grand National for example
- Golf’s two followers limit what a player can have
- Maybe scratch both sides of Hindustani hat
- Help one beat disadvantage
- Husband and I put lid on hamper
- Useful headgear, they say, for a horse race
- Worker in charge has a power restriction
- Give one international a disadvantage
Buddy explains!

The straight part
We know that "bar" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bar = handicap.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 HANDICAP mean?
HANDICAP noun- Something that prevents, hampers, or hinders.
- An allowance of a certain amount of time or distance in starting, granted in a race (or other contest of skill) to the competitor possessing disadvantages; or an additional weight or other hindrance imposed upon the one possessing advantages, in order to equalize, as much as possible, the chances of success.
- (sometimes considered offensive) The disadvantage itself, in particular physical or mental disadvantages of people.
- A race or similar contest in which there is an allowance of time, distance, weight, or other advantage, to equalize the chances of the competitors.
- (card game) An old card game, similar to lanterloo.
- To encumber with a handicap in any contest.
- (by extension) To place at disadvantage.
- To estimate betting odds.