From Latin rapāxrapāc-fromrapereto seizerep- in Indo-European roots
American Heritage Dictionary of the English Language, 5th Edition
Perhaps from rapacity + -ous, in any case ultimately from Latinrapax (“grasping, greedy").
Rapacious Sentence Examples
His rapacious hunger built as his fangs began their descent.
But she appears to have been passionate, exceedingly rapacious and ever careful of her own interest.
However cruel and rapacious the Vikings may have been, the work of disorder and ruin was not all theirs.
He had posed as the defender of the public rights of Europe and won to his side the smaller powers and much of the public opinion of Europe, while the allies were beginning to be regarded more in the light of rapacious conquerors than as disinterested defenders of the liberties of Europe.
These rapacious bugs can produce up to two generations in a season in some areas.