belt · noun C /belt/Full view
belt
A2 a long, thin piece of leather, cloth, or plastic that you wear around your waist
Dictionary examples:

She fastened her belt tightly around her waist.

He had eaten so much that he had to undo his belt.

Learner example:

Juliana gave me a pink belt. (Key English Test; A2; Spanish)

tighten your belt
C2 to try to spend less money
Dictionary example:

Since I lost my job we've all had to tighten our belts.

Learner example:

All this costs money and where do we get this extra money from but from the tax payers, who once again have to tighten their belts. (Certificate of Proficiency in English; C2; Swedish)

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