The most common and most likely answer to this crossword clue is the 9 letter word MINESHAFT
I've seen this crossword clue in Financial Times
M
I
N
E
S
H
A
F
T
More clues leading to the result MINESHAFT
- Descending passage of Wanderer’s has animated this organ
- Passage for those who are boring?
- . Men’s faith is wavering in underground passage
- Network-covered home towards the back not a feature of 4, 21
- Vertical hole he-man ruptured with fist
- He's fit: man working in tunnel underground
- Explosives on lid covering opening of first access tunnel
Buddy explains!
The straight part
We know that "not a feature of 4, 21" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case not a feature of 4, 21 = mineshaft.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 MINESHAFT mean?
MINESHAFT noun- A vertical hole through the strata to reach the mineral which is being mined.