Dastardly (adj): Evil and cruel. (नीचतापूर्ण, कायर)

Synonyms: Iniquitous, Diabolical, Nefarious, Reprehensible
Antonyms: Noble, Praiseworthy, Gallant, Valorous
Example: The villain in the movie is almost always dastardly.

Uses:

It has been proved again at Pulwama, with the most dastardly act perpetrated since the beginning of the 30-year-long proxy war in Jammu and Kashmir.