(linguistics) One of fourteen Arabic letters that cause the "L" of a preceding definite article اَل (al-) to be assimilated in pronunciation. The sun letter suppresses the sound of the "L" and then geminates: al + ṣīn = aṣ-ṣīn. The effect of the sun letter is limited to pronunciation and does not affect the spelling, except that a shadda may be written over the sun letter and in the fully vocalised spelling lām lacks any diacritics: الصِّين (aṣ-ṣīn). The fourteen sun letters are ت (t), ث (ṯ), د (d), ذ (ḏ), ر (r), ز (z), س (s), ش (š), ص (ṣ), ض (ḍ), ط (ṭ), ظ (ẓ), ل (l), ن (n). Phonetically, they represent coronal consonants.

A letter written to a newspaper, magazine or other periodical, usually intended for publication, about issues of concern to readers.

plural of chain letter

A letter that can be mailed successively to different recipients, with each recipient ostensibly (but sometimes sarcastically) being instructed in the body of the letter to mail the letter to another person or persons.

(typography, uncountable) The distinction between majuscule (uppercase) and minuscule (lowercase) letters. / (countable) A case used for carrying written letters.

(education) The humanities, social sciences and natural sciences, considered together.

(idiomatic) Literally, exactly, following the rules as written.

Winter purslane, Montia perfoliata, now Claytonia perfoliata

(calligraphy) A highly calligraphic Western European script style used from approximately 1150.

plural of red-letter day