Toxoid is a bacterial toxin that has been weakened until it is no longer toxic but is strong enough to induce the formation of antibodies and immunity to the specific disease caused by the toxin.

• 内毒素是一类毒性减弱至不再有毒力但仍然具有足够强的抗原性的细菌毒素。它能够诱发肌体产生抗体使对由毒素引起的特异疾病具有免疫力。