Basic Guidelines For English Spellings
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1A person who takes goods by force; a robber, a plunderer, a despoiler.
2A ravenous person or animal; a voracious eater, a devourer; a glutton.
3A person or thing that hungers after (or † for) something. archaic in later use.
Late Middle English; earliest use found in The Wycliffite Bible (early version). Either from ravin + -er, or from raven (although this is first attested later) + -er.