marronnier

French Wikipedia has an article on:

marronnier

Wikipedia ^fr

From marron +‎ -ier.

• IPA^(key): /ma.ʁɔ.nje/

• Audio:

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marronnier m (plural marronniers)

1. chestnut tree
2. horse-chestnut tree
3. (newsmedia, figurative) old chestnut (A news item which, like chestnut fruits, tends to come back every year at the same time. Implies that the news is a fill-in, that might as well have been written in advance.)

• “marronnier”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012.