kick in
B2Informal, but acceptable in semi-formal spoken contexts.
Definition
Meaning
To begin to take effect or become operational, often after a delay.
To contribute (money or effort) to a common cause; (literal) to break something (like a door) by striking it with the foot.
Linguistics
Semantic Notes
Used for processes, sensations, or mechanisms that start, often suddenly or after an expected delay. Carries a sense of inevitability or automatic initiation.
Dialectal Variation
British vs American Usage
Differences
No major syntactic differences. In UK English, 'kick in' might be slightly more common in football (soccer) contexts as a noun (a 'kick-in').
Connotations
Similar in both. The 'contribute money' sense is strongly associated with informal group payments.
Frequency
Slightly higher frequency in American English corpora for the 'begin/start' sense.
Vocabulary
Collocations
Grammar
Valency Patterns
[Something] kicks in. (intransitive)[Someone] kicks in [money/effort]. (transitive, separable)Kick [the door] in. (transitive, separable)Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “The adrenaline kicked in.”
- “Kick in a tenner.”
- “Kick the door in.”
Usage
Context Usage
Business
Informal: 'The new software license will kick in next quarter.'
Academic
Rare, mostly in informal student discourse or describing processes: 'The protective reflexes kick in within milliseconds.'
Everyday
Common: 'I'm waiting for the painkillers to kick in.' 'We all kicked in for a gift.'
Technical
Used in engineering/medicine for describing system/effect initiation: 'The fail-safe mechanism kicked in.'
Examples
By Part of Speech
verb
British English
- The new tax rules will kick in in April.
- Shall we all kick in for the office tea fund?
- The police had to kick the door in.
American English
- My health insurance kicks in next month.
- Everyone kicked in twenty bucks for the gift.
- He kicked the locker in out of frustration.
adjective
British English
- A kick-in competition (football).
American English
- A kick-in amplifier (slang, rare).
Examples
By CEFR Level
- My medicine will kick in soon.
- We kicked in some money for pizza.
- After an hour, the caffeine finally kicked in.
- The team kicked in to help clean up after the event.
- The survival instincts kick in automatically during a crisis.
- They threatened to kick the door in if he didn't open it.
- The full implications of the policy will only kick in after several years.
- Investors were asked to kick in additional capital to keep the project afloat.
Learning
Memory Aids
Mnemonic
Imagine a footballer (kicker) finally entering (in) the game after warming up – his effect on the match BEGINS.
Conceptual Metaphor
STARTING IS APPLYING FORCE (A kick initiates motion).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid direct calque 'ударить внутрь' for the 'begin' sense.
- For 'contribute', don't use 'вложить' (to invest) which implies ownership; use 'сброситься'.
Common Mistakes
- Using it for people starting an action: 'He kicked in to work' is wrong. It's for processes/effects.
- Incorrect separable use: 'The effect kicked the pain in.' (Should be: 'The painkicking effect kicked in.')
Practice
Quiz
In which sentence is 'kick in' used INCORRECTLY?
FAQ
Frequently Asked Questions
It is predominantly informal to neutral. It's common in speech and informal writing but is often replaced by 'begin', 'activate', or 'take effect' in very formal texts.
No, it's not typically used for a person consciously beginning an action (e.g., 'He kicked in to study'). It is used for involuntary processes (instincts, effects) or mechanisms starting automatically.
'Kick in' often implies a noticeable, sometimes sudden start of a (positive or neutral) process or effect (medicine, instincts). 'Set in' usually describes the gradual, often negative, establishment of a state (decay, despair, winter).
Yes, very common in informal group contexts, especially in American English. It implies a casual, often shared contribution (e.g., for a gift, a meal, a fund).