An antiseptic is a substance that stops or slows down the growth of microorganisms. They're frequently used in hospitals and other medical settings to reduce the risk of infection during surgery and other procedures.
 
Some common types of antiseptics include:
alcohols, such as isopropyl alcohol and ethyl alcohol.
quaternary ammonium compound.
chlorhexidine and other diguanides, for use before operations.
antibacterial dye, to treat burns and wounds.
peroxide and permanganate, to disinfect the skin or to use as a mouthwash.