letter, n. initial (first letter).

letter-carrier, n. postman, [mail-carrier], [courier], mail-man, postboy, [post].

letter for letter. literatim.

letters, n. pl. [correspondence].

letters, n. pl. [learning], literature, [erudition], humanities.

let-up, n. (Colloq.) [abatement], assuagement, respite, [subsidence].

let up. (Colloq.) [abate], [subside], [diminish], intermit.

level, a. [even], [flat], [plain], [smooth], [flush], [plumb]; horizontal; [steady], [impartial], well-balanced. Antonyms: undulating [uneven], [concave], [convex], [warped].

level, v. flatten, equalize, [even], [smooth], [reduce]; [raze], [reduce], [overthrow], [demolish]; [adapt], adjust.

lever, n. [pry]. Associated words: fulcrum, [purchase], [prize], prizing.