only

alone, singular, unique

exceptional, extraordinary, rare, uncommon, unusual

A-OK, A1, awesome, bang-up, banner, beautiful, blue-chip, boffo, bonny (also bonnie) [chiefly British], boss [slang], brag, brave, bully, bumper, capital, choice, classic, cool [slang], corking, crackerjack, cracking, dandy, divine, dope [slang], down [slang], dynamite, excellent, fab, fabulous, famous, fantabulous [slang], fantastic, fine, first-class, first-rate, first-string, five-star, frontline, gangbusters (also gangbuster), gone [slang], grand, great, groovy, heavenly, high-class, hot, hype [slang], immense, jim-dandy, keen, lovely, marvelous (or marvellous), mean, neat, nifty, noble, number one (also No. 1), numero uno, out-of-sight [slang], par excellence, peachy, peachy keen, phat [slang], prime, primo [slang], prize, prizewinning, quality, radical [slang], righteous [slang], sensational, splendid, stellar, sterling, superb, superior, superlative, supernal, swell, terrific, tip-top, top, top-notch, wizard [chiefly British], wonderful

better, preferred

exceptional, fancy, high-grade, special

single, solo, unaccompanied, unattended

incomparable, inimitable, matchless, peerless, unequaled (or unequalled), unmatched, unparalleled, unrivaled (or unrivalled), unsurpassable, unsurpassed

distinct, distinctive, individual, separate

nonce

basically, by and large, chiefly, generally, largely, mainly, mostly, predominantly, primarily, principally, substantially

latterly