Craven as an adjective is old-fashioned and rarely used in modern speech. Thou shalt not find a craven knight amongst the noble Sir Lancelot's kin.
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Negative Connotation
Craven implies a strong sense of shamefulness and dishonor in being cowardly. The knight's craven withdrawal from the battle tainted his honor.
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Literary Context
In literature, 'craven' is often associated with Gothic or medieval settings. In the shadowy corridors of the ancient castle, no servant dared to whisper of the lord's craven fear.