The most common and most likely answer to this crossword clue is the 7 letter word NOSEBAG
I've seen this crossword clue in The Guardian
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More clues leading to the result NOSEBAG
- What contains primarily oats, say, easily being consumed by horse?
- Beans go rotten in food container
- Assorted bones: a good source of food for Dobbin?
- What could feed Brummel’s 4, asks Spooner?
- Horse has eaten nothing – surely eyes bulge initially, seeing this?
- Item in a stable country backfiring, some extremists claimed
- Husk of oats and bits of edible bran carried by horse?
- Brush cut up, fed to horse — in this?
- Wine’s bouquet and catch of the day making something worth tucking into
- One might be attached to a horse: keeps blabbering about hugging horse’s back!
Buddy explains!

The straight part
We know that "What could feed" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case what could feed = nosebag.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 NOSEBAG mean?
NOSEBAG noun- A round sack or bag to feed for a horse, mule, ox or alike animal. Usually made of canvas sides and leather bottom slipped over the nose and attached to harness my a strong strap, rope or string. Design to feed animal in public areas and to eliminate spillage from eating.
- Food.
- A curious older woman of other peoples business or affairs.