See craven in Webster's New World Roget's A-Z Thesaurus II
adjective
Ignobly lacking in courage:
chickenhearted, cowardly, dastardly, faint-hearted, lily-livered, pusillanimous, unmanly. (Slang) chicken, gutless, yellow, yellow-bellied. See fear
noun
An ignoble, uncourageous person:
coward, dastard, funk, poltroon. (Slang) chicken, yellow-belly. See fear
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