The most common and most likely answer to this crossword clue is the 6 letter word TIMBER
T
I
M
B
E
R
More clues leading to the result TIMBER
- Row about doctor's deal
- Doctor in row gets deal maybe
- Cuckoo clock perhaps includes British wood
- Row involving Dr Wood
- Watch set round British wood
- River traps a thousand logs
- Foreign banker keeping money for building material?
- Superb finish stopping clock beam
- Feller’s call to take leadership from merchant bankers in Bank
- Piece of wood male found in river
Buddy explains!

The straight part
We know that "Warning" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case warning = timber.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 TIMBER mean?
TIMBER noun- Trees in a forest regarded as a source of wood.
- (outside North America) Wood that has been pre-cut and is ready for use in construction.
- A heavy wooden beam, generally a whole log that has been squared off and used to provide heavy support for something such as a roof.
- Material for any structure.
- The wooden stock of a rifle or shotgun.
- A certain quantity of fur skins (as of martens, ermines, sables, etc.) packed between boards; in some cases forty skins, in others one hundred and twenty. Also timmer, timbre.
- To fit with timbers.
- To construct, frame, build.
- To light or land on a tree.
- To make a nest.
- To surmount as a timber does.
- Used by loggers to warn others that a tree being felled is falling.