milestone

• POS: Noun
• HYPHEN: mile=stone

CIDE DICTIONARY

milestone, n. 

•  A stone serving the same purpose as a milepost.  [1913 Webster]
•  An event or accomplishment marking a significant advance in an endeavor; a notable achievment; as, putting a man in orbit was a major milestone on the way to the moon.  [PJC]

OXFORD DICTIONARY

milestone, n.
1 a stone set up beside a road to mark a distance in miles.
2 a significant event or stage in a life, history, project, etc.

THESAURUS

milestone

bench mark, bookmark, cairn, cardinal point, catstone, chief thing, climax, core, cornerstone, crisis, critical point, crux, essence, essential, essential matter, fundamental, gist, gravamen, great point, heart, high point, important thing, issue, kernel, keystone, landmark, lighthouse, lightship, main point, main thing, mark, marker, material point, meat, menhir, milepost, monument, nub, occasion, pharos, pith, pivot, platform, real issue, salient point, seamark, sine qua non, substance, substantive point, the bottom line, the point, tower, turning point, watchtower

ROGET THESAURUS

milestone

Indication

N indication, symbolism, symbolization, semiology, semiotics, semeiology, semeiotics, Zeitgeist, characteristic, diagnostic, lineament, feature, trait, fingerprint, voiceprint, footprint, noseprint, cloven hoof, footfall, recognition (memory), diagnostic, divining rod, detector, sign, symbol, index, indice, indicator, point, pointer, exponent, note, token, symptom, dollar sign, dollar mark, type, figure, emblem, cipher, device, representation, epigraph, motto, posy, gesture, gesticulation, pantomime, wink, glance, leer, nod, shrug, beck, touch, nudge, dactylology, dactylonomy, freemasonry, telegraphy, chirology, byplay, dumb show, cue, hint, clue, clew, key, scent, signal, signal post, rocket, blue light, watch fire, watch tower, telegraph, semaphore, flagstaff, cresset, fiery cross, calumet, heliograph, guidon, headlight, mark, scratch, line, stroke, dash, score, stripe, streak, tick, dot, point, notch, nick, print, imprint, impress, impression, keyboard symbols, printing symbols, red letter, italics, sublineation, underlining, bold font, jotting, note, annotation, reference, blaze, cedilla, guillemets, hachure, quotation marks, ", double quotes, " ", parentheses, "( )", brackets, "", braces, "", left arrow, "<", right arrow, ">", forward slash, "/", backward slash, "\", exclamation point, "!", commercial at, "@", pound sign, "#", percent sign, "%", carat, "", ampersand, "&", asterisk, "*", hyphen, "-", dash, "-", "_", em dash, "--", plus sign, "+", equals sign, "=", question mark, "?", period, ", ", semicolon, ", ", colon, ":", comma, ", ", apostrophe, "'", single quote, "'", tilde, "~", badge, criterion, countercheck, countermark, countersign, counterfoil, duplicate, tally, label, ticket, billet, letter, counter, check, chip, chop, dib, totem, tessera, card, bill, witness, voucher, stamp, cacher, trade mark, Hall mark, signature, mark, autograph, autography, attestation, hand, hand writing, sign manual, cipher, seal, sigil, signet, hand and seal, paraph, brand, superscription, indorsement, endorsement, password, watchword, catchword, security card, pass, passkey, credentials, open sesame, timbrology, mot de passe, mot du guet, pass-parole, shibboleth, title, heading, docket, address card, visiting card, carte de visite, insignia, banner, banneret, bannerol, bandrol, flag, colors, streamer, standard, eagle, labarum, oriflamb, oriflamme, figurehead, ensign, pennon, pennant, pendant, burgee, blue Peter, jack, ancient, gonfalon, union jack, banderole, old glory, quarantine flag, vexillum, yellow-flag, yellow jack, tricolor, stars and stripes, bunting, heraldry, crest, coat of arms, arms, armorial bearings, hatchment, escutcheon, scutcheon, shield, supporters, livery, uniform, cockade, epaulet, chevron, garland, love knot, favor, beacon, cairn, post, staff, flagstaff, hand, pointer, vane, cock, weathercock, guidepost, handpost, fingerpost, directing post, signpost, pillars of Hercules, pharos, bale-fire, beacon-fire, l'etoile du Nord, landmark, seamark, lighthouse, balize, polestar, loadstar, lodestar, cynosure, guide, address, direction, name, sign, signboard, warning, omen, prefigurement, trace, record, warning &c, alarm, scepter, trophy, gauge, milestone, milepost, brand, fool's cap, check, telltale, test, mileage ticket, milliary, notification, advertisement, word of command, call, bugle call, trumpet call, bell, alarum, cry, battle cry, rallying cry, angelus, reveille, sacring bell, sanctus bell, exposition &c (explanation), proof, pattern, indicating, indicative, indicatory, denotative, connotative, diacritical, representative, typical, symbolic, pantomimic, pathognomonic, symptomatic, characteristic, demonstrative, diagnostic, exponential, emblematic, armorial, individual, known by, recognizable by, indicated, pointed, marked, denotable, indelible, in token of, symbolically, in dumb show, ecce signum, ex ungue leonem, ex pede Herculem, vide ut supra, vultus ariete fortior.