jekyll
C2literary, psychological, figurative
Definition
Meaning
A person whose personality or behaviour radically alternates between two distinct states, one good and one evil.
A representation of a dual or split personality; someone with a hidden, darker side that contrasts sharply with their public persona.
Linguistics
Semantic Notes
This is an eponym derived from the literary character Dr. Jekyll. It functions as a common noun, is typically capitalized (Jekyll), and is almost always paired with 'Hyde' as 'Jekyll and Hyde' when describing a person.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning or usage. The term originates from a British novel and is equally recognized in both varieties.
Connotations
Universally evokes themes of duality, hidden evil, and the Victorian psychology of repression.
Frequency
Slightly higher cultural salience in British English due to the story's origin, but the term is common in educated American English.
Vocabulary
Collocations
Grammar
Valency Patterns
[possessive] + Jekyll (and Hyde)a/the Jekyll in [person]switch/flip from Jekyll to HydeVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “a Jekyll and Hyde (personality/character)”
- “the Jekyll to someone's Hyde”
Usage
Context Usage
Business
Used to describe an executive who is charming with clients but tyrannical with staff.
Academic
Used in literary criticism, psychology, and sociology to discuss duality, identity, and moral conflict.
Everyday
Used to describe someone whose mood or behaviour changes drastically and unpleasantly.
Technical
Rare in hard sciences; used in psychiatry as a cultural reference for Dissociative Identity Disorder (though not a clinical term).
Examples
By Part of Speech
verb
British English
- He seems to Jekyll-and-Hyde his way through meetings, charming one moment and snarling the next. (informal, non-standard)
American English
- Don't Jekyll out on me now; I need your rational side for this negotiation. (highly informal, rare)
adverb
British English
- He acted Jekyllishly polite until the contract was signed.
American English
- She smiled Jekyll-and-Hydely, her eyes not matching her lips. (rare, figurative)
adjective
British English
- His Jekyll-esque demeanour in the office fooled everyone.
American English
- We saw his Jekyllian side at the charity gala, all smiles and handshakes.
Examples
By CEFR Level
- The story is about Dr. Jekyll and Mr. Hyde.
- Sometimes my brother is like Jekyll and Hyde - nice one minute, angry the next.
- The politician was accused of having a Jekyll and Hyde character, presenting one face to the public and another in private.
- Her boss's Jekyll-to-Hyde transformations after 5 PM made the workplace stressful.
- Beneath his philanthropist's exterior lay a veritable Jekyll, whose Hyde emerged in cutthroat business dealings that ruined competitors.
- The novel explores the Jekyll in all of us, the civilised self constantly negotiating with its latent savagery.
Learning
Memory Aids
Mnemonic
Think: 'Jekyll' sounds like 'jackal' (a cunning animal), but he's the respectable 'jacket'-wearing doctor. He's the 'JECK' (check) on his own bad behaviour, which he can't sustain.
Conceptual Metaphor
THE SELF IS A CONTAINER (with a hidden compartment); MORALITY IS A PUBLIC FACADE; THE MIND IS A BATTLEGROUND.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not translate literally as 'Джекилл'. The concept exists as 'Джекил и Хайд' (Dzhekill i Khaid).
- Avoid using it as a simple synonym for 'лицемер' (hypocrite); it implies a more profound, almost monstrous split.
- Remember it is a proper noun used as a common noun, so capitalization is often retained in English.
Common Mistakes
- Using 'Jekyll' alone without 'and Hyde' when first introducing the concept. *'He's a real Jekyll.' (Incomplete) vs. 'He has a Jekyll and Hyde personality.' (Correct).
- Misspelling as 'Jeckyll' or 'Jekyl'.
- Using it to describe simple mood swings rather than a stark moral dichotomy.
Practice
Quiz
In which context is the term 'Jekyll' used most accurately?
FAQ
Frequently Asked Questions
Yes, in most contexts. The term is a fixed binomial pair ('Jekyll and Hyde'). Using 'Jekyll' alone is rare and usually only works if 'Hyde' has already been established in the conversation.
Yes, it is a strongly critical term. It implies they are deceitful, unstable, and have a dangerous hidden nature. Use with caution.
Almost never. 'Jekyll' refers to the 'good' side, but its meaning is entirely dependent on the existence of the 'Hyde' side. It often carries a connotation of being a fragile mask or performance.
It comes from the protagonist, Dr. Henry Jekyll, in Robert Louis Stevenson's 1886 Gothic novella 'Strange Case of Dr Jekyll and Mr Hyde'.