The most common and most likely answer to this crossword clue is the 9 letter word HEARTBURN
I've seen this crossword clue in Financial Times
H
E
A
R
T
B
U
R
N
More clues leading to the result HEARTBURN
- Painful sensation of deer crossing English stream
- Symptom of 3 making bather run amok
- Pick up head of thistle by stream? That’s painful!
- Listen! Consumption before vigorous run gives indigestion
- Discover convert welcoming bishop with ill feeling?
- Catch bout involving start of bilious indigestion
- Try twice to swallow vitamin for painful condition
Buddy explains!
The straight part
We know that "Symptom of 3" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case symptom of 3 = heartburn.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 HEARTBURN mean?
HEARTBURN noun- A burning pain in the chest that is caused by stomach acid entering the gullet.