The most common and most likely answer to this crossword clue is the 7 letter word PLANTED
I've seen this crossword clue in The Daily Telegraph
P
L
A
N
T
E
D
Buddy explains!
The straight part
We know that "fixed" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fixed = planted.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 PLANTED mean?
PLANTED verb- To place (a seed or plant) in soil or other substrate in order that it may live and grow.
- To place (an object, or sometimes a person), often with the implication of intending deceit.
- To place or set something firmly or with conviction.
- To place in the ground.
- To furnish or supply with plants.
- To engender; to generate; to set the germ of.
- To furnish with a fixed and organized population; to settle; to establish.
- To introduce and establish the principles or seeds of.
- To set up; to install; to instate.