[ɪnˈsɪdɪəs], (Adjective)

Definitions:
- proceeding in a gradual, subtle way, but with very harmful effects
(e.g: sexual harassment is a serious and insidious problem)


Phrases:

Origin:
mid 16th century: from Latin insidiosus ‘cunning’, from insidiae ‘an ambush or trick’, from insidere ‘lie in wait for’, from in- ‘on’ + sedere ‘sit’