Chakra is a Sanskrit word and it means “Wheel” or “Vortex” because that is what it looks like when we look at it. Each Chakra is like a solid ball of energy interpenetrating the physical body, in the same way that a magnetic field can interpenetrate the physical body.
The Chakras are not physical, they are the aspects of consciousness in the same way that the Auras are aspects of consciousness. The Chakras are more dense than the Auras but not as dense as the physical body.
Chakras interact with the physical body through two major vehicles, the endocrine system and the nervous system. Each of the seven main Chakras discussed here are associated with one of the seven endocrine glands and also with a particular group of nerves called a Plexus.
Thus, each of these Chakra’s can be associated with particular parts of the body and particular functions within the body controlled by that Plexus or that endocrine gland associated with that Chakra.
BASE/ROOT CHAKRA: reproductive glands. It is the centre of physical energy, grounding and self-preservation. The Root Chakra governs the back, feet, hips, spine and legs.
If you tend to be fearful or nervous, your Root Chakra is probably under-active. You would easily feel unwelcome. If this Chakra is over-active, you may be very materialistic and greedy. You are probably obsessed with being secure and resist change.
SACRAL CHAKRA: sexual organs, bladder, bowel and lower intestine. This Chakra is about feeling and sexuality. When it is open, your feelings flow freely and are expressed without you being over emotional.
If you tend to be stiff and unemotional or have a poker face, the Sacral Chakra is under-active. You are not very open to people. If this Chakra is over active, you tend to be emotional all the time. You will feel emotionally attached to people and can be very sexual.
SOLAR PLEXUS CHAKRA: This Chakra is about asserting yourself in a group. When it is open, you feel in control and you have sufficient self esteem. When this Chakra is under-active you tend to be passive and indecisive.You are probably timid and don’t get what you want. If this Chakra is over-active you are domineering and probably even aggressive.
HEART CHAKRA: As the Heart Chakra is about Love, kindness and affection, when it is open, you are compassionate and friendly, you work at harmonious relationships.
When your Heart Chakra is under-active, you are cold and distant. If this Chakra is over-active, you are suffocating people with your Love and your Love probably has quite selfish reasons.
THROAT CHAKRA: The Throat Chakra governs the throat, thyroid, mouth, teeth, tongue and jaw.
This Chakra is about self expression and talking. When it is open, you have no problems expressing yourself and you might be doing so in a creative way. When this Chakra is under-active, you tend to not speak as much and you probably are introverted and shy. Not speaking the truth may block this Chakra. If this Chakra is over-active, you tend to speak to much, usually to domineer and keep people at a distance. You are a bad listener if this is the case.
THIRD EYE CHAKRA: This Chakra is about insight and visualisation. When it is open, you have a good intuition. You may tend to fantasize. If it is under-active you are not very good at thinking for yourself and you may tend to rely on authoritative people. You may be rigid in your thinking, relying on beliefs too much. You might even get confused easily. If this Chakra is over-active, you may live in a world of fantasy too much. In excessive cases hallucinations are possible.
CROWN CHAKRA: This Chakra is about wisdom and being one with the world. When this Chakra is open, you are unprejudiced and quite aware of the world and yourself.
If it is under-active, you are not very aware spiritually. You are probably quite rigid in your thinking. If this Chakra is over-active, you are probably intellectualising things too much. You may be addicted to spirituality and probably ignoring your bodily needs.
Info from: Healingfromtheheart.co.uk, Timothy Pope.