palette

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A board, typically with a hole for the thumb, which an artist can hold while painting and on which colors are mixed.
• noun The range of colors used in a visual medium, in a picture, or by an artist.
• noun Any similar set of elements or qualities, such as musical notes, used in a medium, in a composition, or by an artist.

from The Century Dictionary.

• noun A thin usually oval or oblong board or tablet with a hole for the thumb at one end, on which a painter lays his pigments when painting.
• noun The set of colors or pigments available for one class or character of work; the set of colors which a painter has on his palette when painting a picture: thus, in ceramics the under-glaze palette is much more limited than the over-glaze.
• noun In metal-working, a breastplate against which a person leans to furnish pressure for the hand-drill.
• noun In medicine: A light wooden spatula used for percussion in massage.
• noun A light splint for the hand.
• noun A small plate protecting the gusset of the armor.
• noun In entomology, a disk-shaped organ formed by three dilated tarsal joints which are closely united.
• noun In ornithology, a parrot of the genus Prioniturus: so called from the conformation of the tail.
• noun In conchology, see pallet, 10.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Paint.) A thin, oval or square board, or tablet, with a thumb hole at one end for holding it, on which a painter lays and mixes his pigments. Hence, any other object, usually one with a flat surface, used for the same purpose.
• noun The complete set of colors used by an artist or other person in creating an image, in any medium. The meaning of this term has been extended in modern times to include the set of colors used in a particular computer application, or the complete set of of colors available in computer displays or printing techniques.
• noun The complete range of resources and techniques used in any art, such as music.
• noun (Anc. Armor) One of the plates covering the points of junction at the bend of the shoulders and elbows.
• noun (Mech.) A breastplate for a breast drill.
• noun a knife with a very flexible steel blade and no cutting edge, rounded at the end, used by painters to mix colors on the grinding slab or palette.
• noun (Paint.) to lay upon it the required pigments in a certain order, according to the intended use of them in a picture.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A thin board on which a painter lays and mixes colours.
• noun The range of colors in a given work or item or body of work.
• noun computing, graphical user interface A visual selection of colours, tools, commands, etc.
• noun A plate of armour covering the points of junction at the bend of the shoulders and elbows.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun board that provides a flat surface on which artists mix paints and the range of colors used
• noun the range of colour characteristic of a particular artist or painting or school of art
• noun one of the rounded armor plates at the armpits of a suit of armor