"The treacherous are ever distrustful," answered Gandalf wearily.
and a dirty treacherous fool.
Yet a treacherous weapon is ever a danger to the hand.
They came upon many hidden pools, and broad acres of sedge waving above wet and treacherous bogs; but Shadowfax found the way, and the other horses followed in his swath.
You nasty treacherous creature.
But it is more treacherous than you are.
At last they came to the end of the black mere, and they crossed it, perilously, crawling or hopping from one treacherous island tussock to another.
And the steps were narrow, spaced unevenly, and often treacherous: they were worn and smooth at the edges, and some were broken, and some cracked as foot was set upon them.
He did not really fear that Faramir would allow Gollum to be killed, but he would probably make him prisoner and bind him; and certainly what Frodo did would seem a treachery to the poor treacherous creature.
There are no more uses of "treacherous" in the book.
Show samples from other sources
The road through Afghanistan’s Kabul gorge is even more treacherous than the Road of Death in Bolivia.
It’s a gorgeous beach, but the waves are treacherous in the water.