The most common and most likely answer to this crossword clue is the 8 letter word PLOUGHED
I've seen this crossword clue in The Guardian
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More clues leading to the result PLOUGHED
Buddy explains!
The straight part
We know that "Failed/ready for new phase of agriculture?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case failed/ready for new phase of agriculture? = ploughed.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.
Crossword Answer definitions
PLOUGHED verb- To use a plough on to prepare for planting.
- To use a plough.
- To have sex with, penetrate.
- To move with force.
- To furrow; to make furrows, grooves, or ridges in.
- To run through, as in sailing.
- To trim, or shave off the edges of, as a book or paper, with a plough.
- (joinery) To cut a groove in, as in a plank, or the edge of a board; especially, a rectangular groove to receive the end of a shelf or tread, the edge of a panel, a tongue, etc.
- (university slang) To fail (a student).
- Turned over with the blade of a plough to create furrows (usually for planting crops).
- Well-trodden or well-researched, previously explored.