The most common and most likely answer to this crossword clue is the 4 letter word SACK
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The straight part
We know that "Varying measure of old/Canary wine" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case varying measure of old/canary wine = sack.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 SACK mean?
SACK noun- A bag; especially a large bag of strong, coarse material for storage and handling of various commodities, such as potatoes, coal, coffee; or, a bag with handles used at a supermarket, a grocery sack; or, a small bag for small items, a satchel.
- The amount a sack holds; also, an archaic or historical measure of varying capacity, depending on commodity type and according to local usage; an old English measure of weight, usually of wool, equal to 13 stone (182 pounds), or in other sources, 26 stone (364 pounds).
- The plunder and pillaging of a captured town or city.
- Loot or booty obtained by pillage.
- A successful tackle of the quarterback behind the line of scrimmage. See verb sense4 below.
- One of the square bases anchored at first base, second base, or third base.
- Dismissal from employment, or discharge from a position, usually as give (someone) the sack or get the sack. See verb sense5 below.
- Bed; usually as hit the sack or in the sack. See also sack out.
- (also sacque) A kind of loose-fitting gown or dress with sleeves which hangs from the shoulders, such as a gown with a Watteau back or sack-back, fashionable in the late 17th to 18th century; or, formerly, a loose-fitting hip-length jacket, cloak or cape.
- A sack coat; a kind of coat worn by men, and extending from top to bottom without a cross seam.
- The scrotum.
- To put in a sack or sacks.
- To bear or carry in a sack upon the back or the shoulders.
- To plunder or pillage, especially after capture; to obtain spoils of war from.
- To tackle the quarterback behind the line of scrimmage, especially before he is able to throw a pass.
- To discharge from a job or position; to fire.
- In the phrase sack out, to fall asleep. See also hit the sack.
- A variety of light-colored dry wine from Spain or the Canary Islands; also, any strong white wine from southern Europe; sherry.
- A bag or pouch inside a plant or animal that typically contains a fluid.
- (games) A sacrifice.
- The privilege, formerly enjoyed by the lord of a manor, of holding courts, trying causes, and imposing fines.
- A bag or pouch inside a plant or animal that typically contains a fluid.
- (games) A sacrifice.
- (games) To sacrifice.
- The privilege, formerly enjoyed by the lord of a manor, of holding courts, trying causes, and imposing fines.