Marked with letters. / Literate (able to read writing in letters). / Educated, especially having a degree (entitled to put an abbreviation such as BS, MA, PhD, MD after a signature).

simple past tense and past participle of letter

plural of letterer

(printing) Obsolete form of literal (“a misprint that affects a letter”). / (Lojban) The name of a letter, such as gy. for the letter G.

One who lets, or lets out. / (archaic) One who retards or hinders.

(transitive) To print, inscribe, or paint letters on something. / (intransitive, US, scholastic) To earn a varsity letter (award).

(historical) Referring to a type of musical notation used by Shakers, based on letters instead of notes. / (rare) Regarding letters of the alphabet.

A symbol in an alphabet. / A written or printed communication, generally longer and more formal than a note.

Third-person singular simple present indicative form of letter

Literature (school subject). / The liberal arts, humanities, learning (broad accumulated cultural knowledge).