assurance · noun /əˈʃʊr.əns/Full view
assurance (PROMISE)
C1 C a promise
Dictionary example:

He gave us his assurance that it would not happen again.

Learner example:

Again, may I give my assurances that the above two requests [for] equipment acquisition would be money well spent for our company. (Certificate in Advanced English; C1; Thai)

assurance (CONFIDENCE)
C2 U confidence
Dictionary example:

He spoke with calm assurance.

Learner example:

"I urge you to stay calm and wait for the rescue team," said Mark with assurance. (Certificate of Proficiency in English; C2; Korean)

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