No colors in the aura are absolute, i.e. different people don't see them in the same way. Colors are simply ways for our minds to understand the different types of pure energy. You don't need to follow these examples of what colors could mean, they are here simply to give your conscious mind some ideas of how to express what your subconscious mind feels.
Black can mean someone who is using a shield. Can also mean a person who is hiding something.
Blue can mean strong intellect, logical thought processes, quiet and calm. Bright blue may mean intuitiveness, whereas dark blue may mean overly analytical nature.
Brown can mean "earthy" person, or someone who is establishing new roots or wants to accomplish something. In small patches can mean an illness beginning in that region.
Gold can mean success in one or more areas of life. It can also mean devotion or divine enlightenment.
Green can mean sympathetic, calm and balanced person. Also on nature lovers. Light green may mean deceitful nature, and dark green may indicate jealousy.
Indigo and Violet can mean a person who is searching for a cause or belief. Dark shades may show that the person has obstacles to overcome and is feeling misunderstood.
Orange is the color of vitality, good health, and excitement. Orange shows lots of energy. People with a lot of orange in their aura tend to be friendly and approachable.
Pink is either physical energy being diffused, or the color of love and romantic nature.
Red can mean physical energy, physically based person, personality or sensuality. It can also mean strong emotions (not necessarily negative emotions).
White usually means a lot of energy sensed. It can also reflect truth and purity and an awakening of greater creativity.
Yellow can reflect new learning opportunities, wisdom and intellect, and the birth of creativity and inspiration. Ruddy yellow may mean that its owner is shy.