Early 19th century; earliest use found in John Lindley (1799–1865), botanist and horticulturist. From scientific Latin achaenium from ancient Greek ἀ- + χαίνειν to gape + scientific Latin -ium.
Definition of achenium in US English:
achenium
nounəˈkiːnɪəm
Botany
Achene.
Origin
Early 19th century; earliest use found in John Lindley (1799–1865), botanist and horticulturist. From scientific Latin achaenium from ancient Greek ἀ- + χαίνειν to gape + scientific Latin -ium.