The Collaborative International Dictionary of English v.0.48:

Ultramarine \Ul`tra*ma*rine"\ ([u^]l`tr[.a]*m[.a]*r[=e]n"), a.
   [Pref. ultra- + marine.]
   Situated or being beyond the sea. --Burke.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Ultramarine \Ul`tra*ma*rine"\, n. [Cf. Sp. ultramarino. So
   called because the lapis lazuli was originally brought from
   beyond the sea, -- from Asia.] (Chem.)
   A blue pigment formerly obtained by powdering lapis lazuli,
   but now produced in large quantities by fusing together
   silica, alumina, soda, and sulphur, thus forming a glass,
   colored blue by the sodium polysulphides made in the fusion.
   Also used adjectively.
   [1913 Webster]

   Green ultramarine, a green pigment obtained as a first
      product in the manufacture of ultramarine, into which it
      is changed by subsequent treatment.

   Ultramarine ash or Ultramarine ashes (Paint.), a pigment
      which is the residuum of lapis lazuli after the
      ultramarine has been extracted. It was used by the old
      masters as a middle or neutral tint for flesh, skies, and
      draperies, being of a purer and tenderer gray than that
      produced by the mixture of more positive colors.
      --Fairholt.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

colorful \colorful\ adj.
   1. having striking color. Opposite of colorless.

   Note: [Narrower terms: changeable, chatoyant, iridescent,
         shot; deep, rich; flaming; fluorescent, glowing;
         prismatic; psychedelic; red, ruddy, flushed,
         empurpled]

   Syn: colourful.
        [WordNet 1.5]

   2. striking in variety and interest. Opposite of colorless
      or dull. [Narrower terms: brave, fine, gay, glorious;
      flamboyant, resplendent, unrestrained; flashy, gaudy,
      jazzy, showy, snazzy, sporty; picturesque]
      [WordNet 1.5]

   3. having color or a certain color; not black, white or grey;
      as, colored crepe paper. Opposite of colorless and
      monochrome.

   Note: [Narrower terms: tinted; touched, tinged; amber,
         brownish-yellow, yellow-brown; amethyst; auburn,
         reddish-brown; aureate, gilded, gilt, gold, golden;
         azure, cerulean, sky-blue, bright blue; bicolor,
         bicolour, bicolored, bicoloured, bichrome; blue,
         bluish, light-blue, dark-blue; blushful,
         blush-colored, rosy; bottle-green; bronze, bronzy;
         brown, brownish, dark-brown; buff; canary,
         canary-yellow; caramel, caramel brown; carnation;
         chartreuse; chestnut; dun; earth-colored,
         earthlike; fuscous; green, greenish, light-green,
         dark-green; jade, jade-green; khaki; lavender,
         lilac; mauve; moss green, mosstone; motley,
         multicolor, culticolour, multicolored, multicoloured,
         painted, particolored, particoloured, piebald, pied,
         varicolored, varicoloured; mousy, mouse-colored;
         ocher, ochre; olive-brown; olive-drab; olive;
         orange, orangish; peacock-blue; pink, pinkish;
         purple, violet, purplish; red, blood-red, carmine,
         cerise, cherry, cherry-red, crimson, ruby, ruby-red,
         scarlet; red, reddish; rose, roseate; rose-red;
         rust, rusty, rust-colored; snuff, snuff-brown,
         snuff-color, snuff-colour, snuff-colored,
         snuff-coloured, mummy-brown, chukker-brown; sorrel,
         brownish-orange; stone, stone-gray; straw-color,
         straw-colored, straw-coloured; tan; tangerine;
         tawny; ultramarine; umber; vermilion,
         vermillion, cinibar, Chinese-red; yellow, yellowish;
         yellow-green; avocado; bay; beige; blae
         bluish-black or gray-blue); coral; creamy; cress
         green, cresson, watercress; hazel; honey,
         honey-colored; hued(postnominal); magenta;
         maroon; pea-green; russet; sage, sage-green;
         sea-green] [Also See: chromatic, colored, dark,
         light.]

   Syn: colored, coloured, in color(predicate).
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

ultramarine
    adj 1: of a brilliant pure blue to purplish blue color
    n 1: blue pigment made of powdered lapis lazuli [syn:
         ultramarine, ultramarine blue]
    2: a vivid blue to purple-blue color