ki
B1Neutral
Definition
Meaning
A small, shaped piece of metal used to open a lock or operate a mechanism.
Something crucial for achieving, accessing, or understanding something else; a vital element or solution.
Linguistics
Semantic Notes
This word functions primarily as a noun but can also be an adjective and a verb, especially in computing (to key in data). The adjective form can mean 'crucial' or 'fundamental'.
Dialectal Variation
British vs American Usage
Differences
No major semantic differences. Minor lexical preferences: UK 'key to the problem', US may also say 'key for the problem'. In sports, 'key player' is common in both.
Connotations
In computing, 'key' as a verb (to input) is used in both varieties. 'Key' (adj.) meaning 'essential' is equally formal.
Frequency
Both noun and adjective uses are high frequency in all registers.
Vocabulary
Collocations
Grammar
Valency Patterns
key (noun) to/of (something)key (adjective) + noun (e.g., key issue)key (verb) + in + data (e.g., key in the details)Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “the key to the city”
- “hold the key to”
- “under lock and key”
- “keyed up (nervous)”
- “key in (to be interested in)”
Usage
Context Usage
Business
Refers to critical success factors, employees, or markets (e.g., 'key performance indicators').
Academic
Used to denote fundamental concepts, arguments, or evidence (e.g., 'key finding').
Everyday
Most common for physical objects (house key, car key) and basic importance (key reason).
Technical
In computing: a button on a keyboard; in databases: a unique identifier; in music: a group of notes.
Examples
By Part of Speech
verb
British English
- Please key in your PIN number.
- She carefully keyed the data into the system.
American English
- He keyed the security code at the door.
- I need to key in my password.
Examples
By CEFR Level
- I can't find my house key.
- Press the 'enter' key on your keyboard.
- Good communication is the key to a strong relationship.
- He is a key player in our team.
- The key argument of the paper centres on sustainable development.
- They haven't yet found the key to deciphering the ancient script.
- The witness provided the key testimony that unlocked the entire case.
- Her research is keyed into the latest theoretical debates in the field.
Learning
Memory Aids
Mnemonic
Think of the KEY you use to open a door; it is KEY (essential) for getting inside.
Conceptual Metaphor
UNDERSTANDING IS UNLOCKING, where a 'key' is the tool that unlocks comprehension.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with Russian 'ки' (Ki) or 'кей' (kei). The English word 'key' sounds like /kiː/, not /kjeɪ/.
- Remember 'key' (adj.) means 'ключевой', not just 'ключ'.
Common Mistakes
- Using 'key of success' instead of the standard 'key to success'.
- Overusing 'key' as an adjective where 'important' or 'main' would be more natural.
- Confusing 'key' with 'quay' (pronounced /kiː/).
Practice
Quiz
Which of the following sentences uses 'key' as a verb?
FAQ
Frequently Asked Questions
'Key to' is the most common and idiomatic collocation for abstract nouns (key to success). 'Key for' is sometimes used, especially when referring to a tool or method for a specific purpose (a key for the cabinet, a key for understanding), but 'key to' is generally preferred and safer.
Yes. It means 'of crucial importance' (e.g., a key issue, a key witness). It is commonly used in formal and informal contexts.
It is considered non-standard by many style guides. As 'key' is an extreme adjective (like 'essential'), intensifiers like 'absolutely', 'really', or 'crucially' are preferred (e.g., 'absolutely key'). However, 'very key' is heard in informal speech.
The most standard and recommended preposition is 'to' (the key to the door, the key to solving the problem). 'For' and 'of' are also possible but less common and can sometimes sound awkward.