The most common and most likely answer to this crossword clue is the 9 letter word RESISTANT
I've seen this crossword clue in The Daily Telegraph
R
E
S
I
S
T
A
N
T
More clues leading to the result RESISTANT
- Rebel worker buried under refuse
- Trying to prevent train sets being laid out wrongly
- Uncooperative Laurel, maybe, interrupts second attempt at exam
- Tough sister, distressed, accepts bronze
- 15 Proof of wanton tartiness
- Proof of saint’s transfiguration in balance
- Hostile sister, unorthodox worker
- MI6, appreciated in Division, finds proof
- Going into raptures is tantalisingly tough
- Rave around sites for development is unaffected
Buddy explains!
The straight part
We know that "tough" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tough = resistant.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 RESISTANT mean?
RESISTANT noun- A person who resists; especially a member of a resistance movement.
- A thing which resists.
- Which makes resistance or offers opposition.
- Which is not affected or overcome by a disease, drug, chemical or atmospheric agent, extreme of temperature, etc.
- Not greatly influenced by individual members of a sample.