gnarly
adj. B2 Upper Intermediate US //ˈnɑɹɫi// UK //nˈɑːli// gnarly
adj. describing something that is very difficult, dangerous, or unpleasant. It can also mean something that is twisted or has a rough, bumpy texture.
adj. describing something that is extremely difficult, dangerous, or unpleasant; also refers to a twisted, knotted, or rough texture. Informal in register, particularly in North American English.
The mountain bike trail is really gnarly today.
After the storm, the old oak tree looked gnarly and twisted, with thick knots in its bark.
The surfers waited for the gnarly waves to break before attempting the dangerous maneuver, knowing that the conditions were far from ideal for beginners.
From gnarl (“knot in wood”) + -y. The slang senses were particularly popularized by US surf culture in the 1970s.