A letter written by one person who is familiar with another, usually a teacher, employer, or person of similar authority, evaluating and often extolling the fitness of the other person for a position.

Particularly significant or positive.

plural of letter of credit

(finance, banking) A document, used primarily in trade finance and issued generally by a financial institution, in which the institution promises to pay debts up to a certain limit to be acquired by the beneficiary against delivery of documents specified in the letter.

A freely distributed letter or pamphlet on routine matters.

plural of open letter

(rare) The letter R, which was trilled in Latin, imitating the sound of a snarling dog.

(singular only) The strict interpretation of the law or rules.

plural of letter bomb

Alternative form of letterbox