brutal

Use brutal to describe something beastly and harsh, like training for a triathlon, a really cold winter in the Arctic, or a mean bouncer at a club who throws people out for no reason.

First used in the mid 15th century to refer to the brutish nature of animals, brutal is now also used to describe other things like human behavior, weather, or even music. “Rock ‘n Roll,” said Frank Sinatra, “is the most brutal, ugly, desperate, vicious form of expression it has been my misfortune to hear.” If someone is brutal, watch out — she's violent and mean. The truth can be brutal, too, if it's something you don't want to hear.