treach·er·ous 
/ˈtrɛtʃərəs/ adjective
/ˈtrɛtʃərəs/ adjective [more treacherous; most treacherous] 1 : not able to be trusted
▪ a treacherous ally/enemy : showing that someone cannot be trusted ▪ a treacherous act of betrayal ▪ treacherous misdeeds 2 : very dangerous and difficult to deal with
▪ sailing through treacherous waters ▪ They were not prepared to hike over such treacherous terrain. ▪ The snow made their hike all the more treacherous. ▪ Discussions about money can lead couples into treacherous territory.
▪ a treacherous ally/enemy : showing that someone cannot be trusted ▪ a treacherous act of betrayal ▪ treacherous misdeeds
▪ sailing through treacherous waters ▪ They were not prepared to hike over such treacherous terrain. ▪ The snow made their hike all the more treacherous. ▪ Discussions about money can lead couples into treacherous territory.
— treach·er·ous·ly adverb
