The most common and most likely answer to this crossword clue is the 5 letter word CHARY
I've seen this crossword clue in The Daily Telegraph
C
H
A
R
Y
More clues leading to the result CHARY
- Cautious cleaning lady ultimately busy
- Cautious about frightening, one having escaped
- Suspicious about husband, Mary scratches head
- Cautious children attached to a line
- Cautious, making love without sex?
- Cautious, cleaner close to canary
- Careful cleaner? Unknown
- Cautious husband being driven barmy, ultimately
- Careful, cleaner close to crockery
Buddy explains!

The straight part
We know that "Cautious" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cautious = chary.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 CHARY mean?
CHARY adverb- In a chary manner.
- Careful, cautious, shy, wary.
- Excessively particular or fussy about details; fastidious.
- Not disposed to give freely; not lavish; frugal, sparing.
- Cared for, regarded as precious; cherished.