What carter and aida said.
I think of jewel tones as the color of those metallic xmas baubles that you hang on your tree that roughly correspond to the color of gemstones. (for example, holiday satin and velvet girls' party dresses used to be in those colors). Heavier silks often come in these colors. Actually a lot of the time you see jewel tones the fabric has a bit of sheen.
Bright is kind of a catch all phrase.
Clear means no gray/brown muting the color - it's like a pure watercolor color.
Deep is a concentrated pigment that is often darker (but usually pure, no black/brown added) and strong, or like you turned up the saturation levels a lot. It's in contrast to a pale color. So darker roses can be deep red or deep pink, the sky can be a deep blue in the evening, etc.
Primary colors are superman red and blue and bright banana yellow.