This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. The silky down attached to the seedlike fruit of a thistle; pappus.

n. The soft, feathery pappus attached to the seeds of a thistle.

n. pappus of a thistle consisting of silky featherlike hairs attached to the seed-like fruit of a thistle

"A thing as important as thistledown is as unimportantly dismissed."

pappus   

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