Skip to main content
treacherous

treacherous

38 7.1
Unstable ground, water, or weather that can suddenly become dangerous
  • adjective
  • /ˈtrɛtʃərəs/
translation icon : traicionero
  • It looks like a paradise, but it is in fact the most treacherous desert in the world--the Kalahari.
  • treacherous terrain
  • treacherous waters
  • treacherous route

Got home, had the long treacherous drive home.

Autoplay Next

Examples

  • The paths are treacherous, even more so after dark, and there is no firewood for making camp.

  • Nedry drives the jeep as fast as he can in the treacherous conditions.

    Fiction book (1993)
  • Got home, had the long treacherous drive home.

  • Darkness is falling, and the way will be treacherous for the horse.

    Fiction book (1999)
  • Oh, the coastal currents off this point are very treacherous.

  • The currents in that passage were notoriously treacherous and the wind undependable.

    Academic text (2012)
  • On they came, weaving and sliding on the treacherous ice underneath the slush.

    Fiction book (1993)
  • The Bering Sea during winter is one of the most treacherous bodies of water in the world.

  • The paths are treacherous, even more so after dark, and there is no firewood for making camp.

  • Road crews are working feverishly to try to make this treacherous morning commute as good as possible.

Synonyms

dangerous
vstreacherous
1.5

Likely to cause harm or injury

focuses on unstable, unpredictable conditions rather than general danger
risky
vstreacherous
269 3.6

Likely to cause loss, harm, or danger

is limited to unstable or unpredictable situations causing likely physical harm
perilous
vstreacherous
43 7.5

Full of danger that could cause harm

is about unstable, unpredictable conditions that are likely to cause harm
dicey
vstreacherous
  • Informal
30 8.5

Likely to be risky or dangerous because the outcome is uncertain

is more formal and refers to unstable conditions likely to cause harm
unreliable
vstreacherous
10 4.3

Not safe because it might fail or break

is specifically unstable and unpredictable, causing harm or difficulty

Antonyms

473 2.3

Not likely to change and stays steady over time

Compounds

Water that is dangerous because of strong currents, hidden rocks or bad weather

How Dangerous

deadly
543 2.8
perilous
43 7.5
treacherous
38 7.1
risky
269 3.6
unsafe
93 1.1

Surface Forms

treacherous positive

Morphology

treacherous = treachery (semi-transparent) = treacher + ous

While formed from the noun 'treachery', the sense referring to physical danger is a figurative extension from untrustworthiness and may not be directly inferable to all learners.

Etymology

Treacherous comes from old words meaning 'to cheat' and is related to treachery and traitor. So, imagine a road or path that 'cheats' you by looking calm but suddenly causing harm, and treacherous describes places that are dangerously unstable.