treacherous

The definition of treacherous is someone who is guilty of dishonesty or betrayal, or something that is dangerous or hazardous.

(adjective)

An example of treacherous is someone you thought was your friend who shares your secrets with everyone.
An example of treacherous is ground made slippery because of an ice storm.

See treacherous in Webster's New World College Dictionary

adjective

characterized by treachery; traitorous; disloyal; perfidious
giving a false appearance of safety or reliability; untrustworthy or insecure: treacherous rocks

Origin: ME trecherous < OFr trecheros

Related Forms:

See treacherous in American Heritage Dictionary 4

adjective

Marked by betrayal of fidelity, confidence, or trust; perfidious. See Synonyms at faithless.
Not to be relied on; not dependable or trustworthy.
Marked by unforeseen hazards; dangerous or deceptive: treacherous waters.

Related Forms: