The most common and most likely answer to this crossword clue is the 6 letter word RATION
R
A
T
I
O
N
More clues leading to the result RATION
- Restrict speech with introduction missing
- One in shop is helping
- Fixed allowance of one sailor back working
- Budget speech lacking nothing
- Hunter blowing top about a time limit
- Helping one to enter shop
- Country has new leader, making allowance
- Harangue not initially helping
- Limit relationship with knight
- Helping informer, one is charged
Buddy explains!

The straight part
We know that "Fixed allowance" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fixed allowance = ration.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 RATION mean?
RATION noun- A portion of some limited resource allocated to a person or group.
- To supply with a ration; to limit (someone) to a specific allowance of something.
- To portion out (especially during a shortage of supply); to limit access to.
- To restrict (an activity etc.)