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Results found in several dictionaries: Collins, Business, Collaborative Dictionary
lettre de remerciement 
  nf thank-you letter

lettre de remerciement   n f thank-you letter

Collaborative Dictionary     French-English
lettre de remerciement n. thank-you letter ~ 
lettre d'accompagnement nm. cover letter Reverso General Dictionary 
lettre d'avis nm. letter of notification Reverso General Dictionary 
lettre de recommandation nm. letter of recommendation Reverso General Dictionary 
lettre de demande d'emploi nm. job application letter Reverso General Dictionary 
lettre d'excuse n. letter of apology ~ 
lettre d'invitation n. invitation ~ 
lettre de voiture n. waybill ~ 
lettre d'affaires nm. business letter Reverso General Dictionary 
lettre d'information n. newsletter ~ 
lettre recommandée n. registered letter ~ 
lettre de procuration nm. letter of proxy Reverso General Dictionary 
lettre de réclamation nm. letter of complaint Reverso General Dictionary 
lettre de transport aérien n. air waybill ~ 
lettre recommandée avec a.r n. registered letter with recorded delivery ~ 
lettre recommandée avec accusé de réception nm. registered letter with recorded delivery Reverso General Dictionary 
lettre de cadrage nm. guideline document Reverso General Dictionary 
lettre de candidature nm. letter of application Reverso General Dictionary 
lettre de change nm. bill of exchange Reverso General Dictionary 
lettre de sommation n. letter of summons ~ 
licence ès lettres n. aha aha 
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'lettre de remerciement' also found in translations in English-French dictionary
become a dead letter v. 1) devenir lettre morte (vi), 2) devenu lettre morte (part II vi) Reverso General Dictionary 
by way of thanks adj. en guise de remerciements Reverso General Dictionary 
air waybill n. la lettre de transport aérien Reverso General Dictionary 
insurance binder n. la lettre de couverture Reverso General Dictionary 
letter of support n. la lettre de soutien Reverso General Dictionary 
letters of support n. les lettres de soutien Reverso General Dictionary 

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