The most common and most likely answer to this crossword clue is the 7 letter word LACTEAL
I've seen this crossword clue in The Times
L
A
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More clues leading to the result LACTEAL
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The straight part
We know that "Milky" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case milky = lacteal.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 LACTEAL mean?
LACTEAL noun- (chiefly in plural) Each of the lymphatic vessels which convey chyle from the mesentery to the thoracic duct.
- One of the lactiferous ducts or other components of milk-producing organs.
- Relating to milk.
- Relating to milk production.
- Relating to, or containing, chyle.