What does light mean in Tae Kwon Do?

Answer 1

You might need to be more specific in what you mean by "light," but the term is often used in Taekwondo to describe a level of contact when striking a target (either inanimate target or live person). "No contact" refers to kicks and punches, usually in sparring, where you execute full power, stopping just short of the target without touching. "Light contact" is where you touch the target, but do not make enough impact to move it, or injure the person. "Medium contact" would slightly jar the target, or move a person, but still not hurt them. "Heavy contact" abruptly displaces the target or person, and could cause minor or severe injury if protective padding is not used. "Full contact" is a term that is often misused (usually to incorrectly describe heavy contact), and is the maximum amount of power that the attacker is capable of delivering. This means no restraint, and no "pulling" of the shot. It can result in severe injury, or death to a person who is the recipient, even when standard protective gear is used.

"Excessive contact" is any level of contact that goes beyond the rules of a particular engagement or competition. This often results in warnings, deduction of points, or disqualification of the offending attacker. In competition, valid points are usually not awarded when the technique is ruled by the officials as using excessive contact. Occasionally a tournament that allows medium to heavy contact will still disqualify a competitor if they draw blood, even if the contact was only light.

[note: If this is not what you meant by "light," then please clarify, and I will edit my answer]