Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles often occur all over the plant - on surfaces such as those of the stem and flat parts of leaves. These are an adaptation that protects the plant against herbivorous animals, discouraging them from feeding on the plant.
In the language of flowers, the thistle (like the burr) is an ancient Celtic symbol of nobility of character as well as of birth, for the wounding or provocation of a thistle yields punishment. For this reason the thistle is the symbol of the Order of the Thistle, a high chivalric order of Scotland.
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