The most common and most likely answer to this crossword clue is the 8 letter word HORNBEAM
I've seen this crossword clue in The Times
H
O
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N
B
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M
More clues leading to the result HORNBEAM
- Wanting opening? Cut a bit of light white wood
- Grin broadly after antler found in wood
- Wood producer placing shaft on cape
- Warning device has to emit light in tree
- Instrument ray finds timber source
- Hardwood tree, note, coated with old frostiness in the morning
- Arm bone fractured beneath hard wood
- Source of timber in conversion of barn and home
- Wood that can make wind instrument and timber
- Model makers cut each minute tree
Buddy explains!

The straight part
We know that "white wood" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case white wood = hornbeam.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 HORNBEAM mean?
HORNBEAM noun- A tree of the genus Carpinus, having a smooth gray bark and a ridged trunk, the wood being white and very hard, common along the banks of streams in the United States.
- A hop hornbeam (Ostrya virginiana).
- The wood of these trees.