The most common and most likely answer to this crossword clue is the 5 letter word SKEIN
S
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N
More clues leading to the result SKEIN
- Geese flying east into cover
- Flock seen aloft with grouse finally breaking cover
- Birds flying, seen from hide around edge of lake
- Birds flying east into Hull
- Hank Williams’s last relatives touring Europe
- English hidebound, in a tangle?
- Birds in flight seen from base in hide
- Hank Williams finally getting school punishment in report?
- Geese flying east in film
- Woolly lot of wild geese
Buddy explains!

The straight part
We know that "A bit of yarn" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a bit of yarn = skein.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 SKEIN mean?
SKEIN noun- A quantity of yarn, thread, or the like, put up together, after it is taken from the reel. A skein of cotton yarn is formed by eighty turns of the thread around a fifty-four inch reel.
- A web, a weave, a tangle.
- The membrane of a fish ovary.
- (wagonmaking) A metallic strengthening band or thimble on the wooden arm of an axle.
- (provincial England) A group of wild fowl, (e.g. geese, goslings) when they are in flight.
- A winning streak.
- To wind or weave into a skein.