insidious
/ɪnˈsɪdiəs/ (bre, ipa) · /ɪnˈsɪdiəs/ (ame, ipa) · /in-ˈsi-dē-əs/ (ame, mw)
insidious — adjective
- insidiouspositive
- more insidiouscomparative
- most insidioussuperlative
1. Something that is insidious spreads or develops slowly and in a hidden way, caus
Something that is insidious spreads or develops slowly and in a hidden way, causing serious harm that is not noticed until it is too late to stop it.
High blood pressure is an insidious condition that can damage the heart and blood vessels for years with no symptoms.
insidious condition — illness that progresses unnoticed
The insidious spread of false information on social media slowly made people distrust all news sources.
insidious spread of [something harmful]
Hana noticed an insidious pattern of small lies that gradually destroyed her friendship with Mei-Lin.
The insidious effects of poor diet and lack of exercise often take decades to become visible.
Diego discovered that the mold behind the walls had an insidious way of spreading through the entire building.
- stealthy
focuses on the secrecy of movement or action; 'stealthy' is often about avoiding detection in a specific moment, while 'insidious' implies gradual, long-term harm
- subtle
less negative; 'subtle' simply means hard to notice, while 'insidious' carries the strong sense of resulting harm
- pernicious
more formal and stronger; 'pernicious' emphasises the destructive effect itself, while 'insidious' emphasises the hidden, gradual way harm happens
用法筆記
Subject is typically a condition, process, or influence whose harmful effects accumulate slowly — not used for immediate or obvious threats.
常見錯誤
2. Describes a person or action that secretly waits for the right moment to trap, d
Describes a person or action that secretly waits for the right moment to trap, deceive, or harm someone through dishonest and hidden methods.
An insidious colleague had been quietly spreading lies about Binta to ruin her chances of promotion.
The spy used insidious methods to turn team members against each other over many months.
insidious methods — dishonest tactics to harm others
Guo warned the others about the insidious tricks their competitor was using to steal their customers.
Pablo later discovered that his so-called friend had plotted an insidious plan to take over his business.
- treacherous
more direct and personal; 'treacherous' describes someone who betrays trust, while 'insidious' focuses on the hidden, gradual method of the betrayal
- deceitful
emphasises the act of lying or hiding the truth; 'insidious' adds a sense of patient, long-term scheming
- crafty
slightly less formal; 'crafty' suggests clever trickery that may not be as harmful as 'insidious' implies
- honest
an honest person deals openly and fairly — the opposite of someone who secretly plots
- straightforward
straightforward actions are direct and clear, unlike insidious scheming
用法筆記
Distinguish from sense 1 (SUBTLE HARM): sense 2 focuses on deliberate, deceptive human intent to entrap, whereas sense 1 describes impersonal processes or conditions that cause harm passively.
常見錯誤
3. Describes something that seems attractive, pleasant, or desirable on the surface
Describes something that seems attractive, pleasant, or desirable on the surface, but secretly causes harm or leads people to make bad choices.
The insidious charm of the advertisement made children beg for toys their parents could not afford.
insidious charm — surface attraction that hides harm
Suki was drawn to the insidious promises of a part-time job that claimed to pay ten times the normal wage.
Qing saw through the insidious appeal of the investment scheme, which sounded too good to be true.
The insidious allure of fast money led many young people into a trap that cost them their savings.
- seductive
focuses on the power to attract; 'seductive' can be neutral or positive, while 'insidious' always implies hidden harm
- alluring
emphasises the power of attraction without necessarily implying danger; 'insidious' makes clear that the attraction is a trap
- deceptively attractive
a phrase rather than a single word; like 'insidious', it highlights the gap between surface appeal and actual danger
用法筆記
Distinguish from sense 1 (SUBTLE HARM): sense 3 involves active appeal or attraction that draws people in, whereas sense 1 describes a neutral process that simply goes unnoticed. The object of the attraction believes they are making a good choice.