The most common and most likely answer to this crossword clue is the 7 letter word OFFHAND
I've seen this crossword clue in Financial Times
O
F
F
H
A
N
D
More clues leading to the result OFFHAND
- Not on, worker being so casual!
- Casual assistance given to cricket side
- Casual worker following start of race
- Casual worker not working at first
- Casual worker appears after not working
- Without thought for sick worker
- Cavalier has gone to help
- Rotten worker — and so rude!
- Cancelled by Henry, with or without consideration
- Not at work, employee rude
Buddy explains!

The straight part
We know that "Without thought" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case without thought = offhand.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 OFFHAND mean?
OFFHAND adjective- Without planning or thinking ahead.
- Careless; without sufficient thought or consideration.
- Curt, abrupt, unfriendly.
- Right away, immediately, without thinking about it.
- In an offhand manner.