Would this be a legal way to play Fell Specter?

I’m trying to make a Mill deck for MTG, and looking at Fell Specter, it seems like a really good combo card. However, the card reads that the effect only happens when your opponent discards. So does milling count as discarding or does discarding only refer to form their hand?


The word "discard" is defined in MtG as the act of moving a card from the hand directly to the graveyard. Milling does not count.