thin · adjective /θɪn/Full view
Nouns: thinner
Adjectives: thin
Verbs: thin
Adverbs: thinly
thin (NOT THICK)
A2 Something that is thin is smaller than usual between its opposite sides.
Dictionary examples:

a thin slice of meat

The walls are very thin.

a thin jacket

Learner example:

Wear some thin clothes because it will be very hot. (Key English Test; A2; Chinese)

thin (NOT FAT)
A2 A thin person or animal has very little fat on their body.
Dictionary examples:

She's too thin.

Thin, hungry dogs roam the streets.

Learner example:

He's tall, thin and he has got black hair and black eyes. (Preliminary English Test; B1; Italian)

wear thin
C2 If a feeling or explanation starts to wear thin, it becomes weaker or harder to accept.
Dictionary example:

I've warned you several times about being late and my patience is wearing thin.

Learner example:

Hardly could they fight against others, when their own convictions had started to wear thin. (Certificate of Proficiency in English; C2; Catalan)

vanish into thin air
C2 to suddenly disappear in a mysterious way
Dictionary example:

He was walking ahead of me on the path and then he just vanished into thin air.

Learner example:

The fact is that vacations are not problem-solving, and whatever one wants to leave behind does not vanish into thin air, it just lurks in the corner of your mind until the return date. (Certificate of Proficiency in English; C2; Spanish)

thin · noun /θɪn/
through thick and thin
C2 If you support or stay with someone through thick and thin, you support or stay with them in both easy and difficult situations.
Dictionary example:

She'd stuck by Neil through thick and thin.

Learner example:

As I had neither friends nor parents who could stand by me through thick and thin, this diary meant a lot to me. (Certificate of Proficiency in English; C2; Spanish)

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