noun

• (countable) Any of several, generally large and lustrous black species of birds in the genus Corvus, especially the common raven (Corvus corax).
  "Some ſay that Rauens foſter forlorne children, / The vvhilſt their ovvne birds famiſh in their neſts: / Oh be to me though thy hard hart ſay no, / Nothing ſo kinde but ſomething pittifull."

verb

• (transitive; sometimes intransitive with "from", "away", etc; archaic) To obtain or seize by violence; to plunder.
  "[…] ravening and destroying his goodes, they spoyled his wife and chyldren of all theyr apparell […]"
• (transitive, intransitive, sometimes with "up", "down", "in", etc) To devour with great eagerness; to feed (on something) hungrily or greedily.
  "And the hound Time, when all the Worlds and cities are swept away whereon he used to raven, having no more to devour, shall suddenly die."
• (transitive; intransitive with "on") To prey on with rapacity; to attack with violence in order to, or as if to, devour.
  "I refer to the danger of keeping a dog of this nature and disposition in a bedroom, where it can spring out ravening on anyone who enters."
• (intransitive) To show rapacity; to be greedy (for something).
  "[…] because hogs are commonly rauening for their meat, more then other cattel, it is meet therefore to haue them ringed, or else they wil doe much hurt in digging and turning vp corne fieldes […]"