Botryoidal (adjective)
botryoidal [bo-tree-oid-l]

adjective, Mineralogy.
1. having the form of a bunch of grapes: botryoidal hematite.

Also, botryose.

Origin: 1810-20; < Greek botryoeid (ḗs) shaped like a bunch of grapes ( bótry (s) bunch of grapes + -oeidēs -oid ) + -al

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