The most common and most likely answer to this crossword clue is the 5 plus 5 letter word TREAD WATER
I've seen this crossword clue in The Times
T
R
E
A
D
W
A
T
E
R
More clues leading to the result TREAD WATER
- Make no progress, but hold one’s head up mainly
- Get nowhere, seeing doctor possibly pocketing extraordinary wad
- Fail to make any progress, as war treated suspiciously
- Hold off undoing treat, reward Romeo’s left
- Collapse of art trade we just survive
- Get nowhere fast in current circumstances?
- Make no progress in the main
- We dart and tear all over the place, but fail to make progress!
- Heartless type in trade war struggling to stand still
- Wait for rain after March?
Buddy explains!
The straight part
We know that "fail to progress" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fail to progress = tread water.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.