beastly
adj.extremely bad, unpleasant, or annoying. You use this to describe something that is very difficult to deal with, like a long journey or a cold day.
adj.extremely unpleasant, disagreeable, or difficult. Often used to describe weather, travel, or general circumstances that are particularly burdensome.
“The journey was beastly because of the heavy rain.”
“I had a beastly morning at the office, dealing with a broken printer and a missed train.”
“The hikers found the ascent beastly, as the thin mountain air and steep incline made every step feel like a monumental effort.”
From Middle English beestly, bestely, beastelich, equivalent to beast + -ly. Compare West Frisian bistachtich (“beastly”), Dutch beestachtig (“beastly”), German biestig (“beastly”).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.