The most common and most likely answer to this crossword clue is the 9 letter word MUSHROOMS
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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.
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What does MUSHROOMS mean?
MUSHROOMS noun- Any of the fleshy fruiting bodies of fungi typically produced above ground on soil or on their food sources (such as decaying wood).
- A fungus producing such fruiting bodies.
- Champignon or Agaricus bisporus, the mushroom species most commonly used in cooking.
- Any of the mushroom-shaped pegs in bar billiards.
- A concrete column with a thickened portion at the top, used to support a slab.
- One who rises suddenly from a low condition in life; an upstart.
- Something that grows very quickly or seems to appear suddenly.
- To grow quickly to a large size.
- To gather mushrooms.
- To form the shape of a mushroom.