midnight

mid‧night S3 /ˈmɪdnaɪt/ BrE AmE noun [uncountable]
[Word Family: noun: ↑night, ↑midnight, ↑nightie; adverb: ↑overnight, ↑nightly; adjective: ↑nightly, ↑overnight]
12 o'clock at night ⇨ midday
at midnight
The train is due in at midnight.
after/before midnight
We stayed there until way after midnight.
You can’t phone her now – it’s gone midnight (=after midnight)!
By the time he arrived, it was well past midnight (=after midnight).
at/on the stroke of midnight (=at exactly midnight)
The treaty will come into force on the stroke of midnight tonight.
He’s gone for a midnight swim.
► Do not say ‘in the midnight’. If you mean ‘at 12 o’clock at night' say at midnight and if you mean ‘very late at night’ say in the middle of the night.

Oxford Advanced Learner's Dictionary

midnight

mid·night [midnight midnights] [ˈmɪdnaɪt] [ˈmɪdnaɪt] noun uncountable
1. 12 o'clock at night
• They had to leave at midnight.
• on the stroke of midnight/shortly after midnight
• She heard the clock strike midnight.
• Let's have a midnight feast tonight (= a secret meal that children like to have in the middle of the night).

• We have to catch the midnight train.

2. (especially NAmE) = midnight blue
see burn the midnight oil at burn _v., do a moonlight/midnight flit at flit _n.
Word Origin:
Old English midniht (see mid-, night).
Example Bank:
• Downstairs in the hall, midnight struck.
• It was approaching midnight when I finally reached home.
• On the stroke of midnight, Prince Charming turned back into a rat.
• The church clock struck midnight.
• the land of the midnight sun
• The law comes into effect on the stroke of midnight tomorrow.
• The ship set sail shortly after midnight.

• They had to leave at midnight.

Cambridge Advanced Learner's Dictionary

Cambridge Advanced Learner's Dictionary - 4th Edition

midnight / ˈmɪd.naɪt / noun [ U ]

A2 twelve o'clock in the middle of the night:

There's a great film on TV at midnight.

It was after midnight when we got home.

Collins COBUILD Advanced Learner’s English Dictionary

midnight

/mɪdnaɪt/

Frequency: The word is one of the 3000 most common words in English.

1.
Midnight is twelve o’clock in the middle of the night.
It was well after midnight by the time Anne returned to her apartment...
N-UNCOUNT: usu prep N

2.
Midnight is used to describe something which happens or appears at midnight or in the middle of the night.
It is totally out of the question to postpone the midnight deadline...
ADJ: ADJ n

3.
If someone is burning the midnight oil, they are staying up very late in order to study or do some other work.
Chris is asleep after burning the midnight oil trying to finish his article.
PHRASE: V inflects

Merriam-Webster's Advanced Learner's Dictionary

Merriam-Webster's Advanced Learner's Dictionary:

midnight

mid·night /ˈmɪdˌnaɪt/ noun [noncount] : the middle of the night : 12 o'clock at night
• Her parents wanted her home before midnight.
• The clock struck midnight.
• It was 12 midnight when we arrived home.
- often used before another noun
• a midnight snack
• at the midnight hour [=at midnight]
burn the midnight oil