recreant

Adjective

• lacking even the rudiments of courage; abjectly fearful
  • the craven fellow turned and ran
    
  • a craven proposal to raise the white flag
    
  • this recreant knight- Spenser
    

• having deserted a cause or principle
  • some provinces had proved recreant
    
  • renegade supporters of the usurper
    

Noun

• a disloyal person who betrays or deserts his cause or religion or political party or friend etc.

• an abject coward

Related words

• Synonyms: 
  craven , renegade , deserter , apostate , turncoat , ratter , poltroon