1. In Christian theology, a group of vices considered the most serious moral failings: pride, greed, lust, envy, gluttony, wrath, and sloth
   "The seven deadly sins are often depicted in medieval art and literature"
    
2. [informal] Any set of fundamental transgressions or faults in a particular field or context
   "The seven deadly sins of public speaking include lack of preparation and poor body language"

Encyclopedia: Seven deadly sins