Envy is an emotion experienced by one who intensely desires something possessed by another. The basis of envy is the desire to possess, not the desire to deprive others, although if the object in question is the only one available then deprivation will be consequential.
Envy is often associated with the colour green, as in "green with envy". The phrase "green-eyed monster" refers to an individual whose current actions appear motivated by envy.
Envy is generally considered an unpleasant emotion to feel, as well as being responsible for unpleasant behaviour towards others. Historically it has been listed as one of the seven deadly sins.