lock
gb/lˈɑk/ us/lˈɑk/
A1
English
~ 2400
Senses
0 senses
Verb
A1
action
1
Fasten something with a lock
To close something with a lock so it cannot be opened without a key or code.
Usage pattern:
to lock [something]
Common mistake:
Learners sometimes confuse 'lock' with 'close'; 'close' means to shut but not necessarily secure with a lock.
Synonyms
secure (More general; can mean to make safe in other ways, not just with a lock.)
Antonyms
unlock (The direct opposite—means to open something that is locked.)
Collocations
lock the door
|lock the gate
|lock your car
Themes
daily life
|security
|daily_life
|housing
|core_vocabulary
Examples
- Please lock the front door before you leave.
- She locked her bike to the fence.
- They locked the safe after putting the documents inside.
- I forgot to lock my car last night.
- He quickly locked the drawer when someone knocked.
Learner examples
- Lock the door when you go out.
- I lock my bike at school.
- Please lock the window.
- We lock our car at night.
Noun
A1
entity
2
Device that fastens something closed
A thing that keeps a door, gate, etc. closed and needs a key or code to open it.
Synonyms
fastener (General term for something that holds things together; not necessarily for security.)
Antonyms
latch (A simple fastening device that may not require a key; less secure than a lock.)
Collocations
door lock
|padlock
|combination lock
Themes
daily life
|security
|daily_life
|housing
|technology
Examples
- The lock on the front door is broken.
- He installed a new lock on his bike.
- This suitcase has a built-in lock.
- Can you fix the lock on the gate?
- She forgot the combination to her lock.
Learner examples
- The lock is broken.
- I have a new lock for my bike.
- This box has a lock.
- We need to fix the lock.
Verb
B1
state
3
Become fixed in position
To stop moving and stay in one position, often because something is stuck.
Usage pattern:
[something] locks into place
Synonyms
jam (Informal; often refers to machinery or parts getting stuck.)
Antonyms
loosen (Means to make less tight or fixed.)
Collocations
lock into place
|lock together
|lock up
Themes
mechanics
|daily life
|daily_life
|core_vocabulary
Examples
- The gears locked and the machine stopped working.
- Her knees locked during the race.
- The folding legs lock into place when opened.
- The steering wheel locked after I removed the key.
Learner examples
- The wheel locked suddenly.
- The door locks when it closes.
- My computer locked and I could not type.
Noun
technical
B2
entity
4
Chamber for raising/lowering boats
A part of a canal with gates that moves boats up or down to match water levels.
Synonyms
sluice gate (Similar water-control structure but not necessarily for boats.)
Collocations
canal lock
|pass through a lock
|lock gate
Themes
transport
|engineering
|travel
|transportation
Examples
- The boat entered the lock to be raised to the next level.
- Engineers repaired the old canal lock.
- We waited while another ship passed through the lock.
Learner examples
- The boat is in the lock.
- A man opens the lock gate.
- The ship goes through the lock.
Noun
B2
entity
5
Small group of hairs together
A small piece of hair that grows or hangs together.
Synonyms
strand (Refers generally to one thin piece of hair or thread; less poetic than 'lock'.)
Collocations
a lock of hair
|golden locks
Themes
appearance
|body
|daily_life
Examples
- He brushed a lock of hair from her face.
- She cut off a lock of her hair as a keepsake.
- Golden locks framed the child's face.
Learner examples
- She has a lock of hair on her face.
- He cut a lock of hair.
- I see a long lock of hair.
Grammar
Dictionary form
lock
IPA
GB/lˈɑk/
US/lˈɑk/
Syllables & stress
lock (1 syllable)
Stress on 1st syllable (lock)
Word forms
Noun
- Base: lock
- Plural: lock, locks
Verb
- Base: lock
- 3rd Person Singular: locks
- Present Participle: locking
- Past: locked
Word family
Expressions
lock in
1/lˈɑk ˈɪn/
phrasal verb
Secure inside by locking doors/barriers
To keep someone or something inside by locking doors or gates.
Examples
- They locked the dog in for the night.
- Protesters were accidentally locked in the building.
lock out
1/lˈɑk ˈaʊt/
phrasal verb
Prevent entry by locking doors/barriers
To stop someone from entering by locking doors or gates.
Examples
- I forgot my keys and locked myself out.
- They locked out the workers during the strike.
lock up
1/lˈɑk ˈʌp/
phrasal verb
Secure completely by locking
To close and lock all doors and windows before leaving or going to bed.
Examples
- Don't forget to lock up before you leave tonight.
- They always lock up the shop at 8 p.m.
lock horns
1/lˈɑk hˈɔɹnz/
idiom
Engage in direct conflict or argument
To get into an argument or fight with someone.
Examples
- The two leaders locked horns over trade policy.
- The two candidates locked horns over healthcare policy in the debate.
- They often lock horns during meetings.
- He often locks horns with his manager about how to run the team.
under lock and key
1/ˈʌndɚ lˈɑk ˈænd kˈi/
idiom
Kept securely locked away
Kept somewhere safe and locked so no one can get it easily.
Examples
- The jewels are kept under lock and key at all times.
- The jewels are kept under lock and key.
- Sensitive documents should be under lock and key.
- Important documents are stored under lock and key.