acumen C2 Topic:Register & Style US /əˈkjumən/ UK /ˈækjʊmən/ See IPA manual Freq #39171 Meanings 1 noun A bony, often sharp, protuberance, especially that of the ischium. The rostrum is the anterior extension of the carapace between the eyes. It ends in a more or less acute tip, or acumen, and may have a lateral spine on each side or bear a longitudinal keel (carina) on the dorsal surface. Etymology Borrowed from Latin acūmen (“sharp point”). Topics Register & Style External links Cambridge Dictionary Wiktionary Google Images # acumen **Type:** Word **Level:** C2 **Part of speech:** noun **IPA (US):** /əˈkjumən/ **IPA (UK):** /ˈækjʊmən/ **Frequency rank:** 39171 ## Meanings 1. A bony, often sharp, protuberance, especially that of the ischium. ## Examples - The rostrum is the anterior extension of the carapace between the eyes. It ends in a more or less acute tip, or acumen, and may have a lateral spine on each side or bear a longitudinal keel (carina) on the dorsal surface. ## Etymology Borrowed from Latin acūmen (“sharp point”). ## Topics - Register & Style markdown