achene

noun

(Gr. a-: without; khainen: to open) A dry, indehiscent fruit formed from a superior ovary of one carpel and containing one seed, attached to the fruit wall at one point only, which is free from the pericarp (often applied, less correctly, to the one-seeded fruits of Asteraceae). An example is the feathery achene of clematis, a strawberry pip. Variants of the achene include the caryopsis, cypsela, nut, and samara. (Also written akene). See also etaerio.