The most common and most likely answer to this crossword clue is the 8 letter word PERSPIRE
I've seen this crossword clue in The Daily Telegraph
P
E
R
S
P
I
R
E
More clues leading to the result PERSPIRE
- Drip from a steeple
- Sweat as Neuschwanstein’s architect suggests how fee should be calculated
- Salesperson climbing church feature to suffer in the heat?
- Dad in Paris tears round in sweat
- Exhibit siigns of exertion seeing column on exercise runs
- Break into a sweat for each peak
- Go into liquidation when working hard
- Each peak will make one sweat
- On tower, short person produces sweat
Buddy explains!

The straight part
We know that "Exhibit siigns of exertion" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case exhibit siigns of exertion = perspire.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 PERSPIRE mean?
PERSPIRE verb- To emit (sweat or perspiration) through the skin's pores.
- To be evacuated or excreted, or to exude, through the pores of the skin.